Miglioramenti alla sicurezza

Android migliora continuamente le proprie funzionalità e offerte in materia di sicurezza. Consulta le di miglioramenti per release nel riquadro di navigazione a sinistra.

Android 14

Every Android release includes dozens of security enhancements to protect users. Here are some of the major security enhancements available in Android 14:

  • Hardware-assisted AddressSanitizer (HWASan), introduced in Android 10, is a memory error detection tool similar to AddressSanitizer. Android 14 brings significant improvements to HWASan. Learn how it helps prevent bugs from making it into Android releases, HWAddressSanitizer
  • In Android 14, starting with apps that share location data with third-parties, the system runtime permission dialog now includes a clickable section that highlights the app's data-sharing practices, including information such as why an app may decide to share data with third parties.
  • Android 12 introduced an option to disable 2G support at the modem level, which protects users from the inherent security risk from 2G's obsolete security model. Recognizing how critical disabling 2G could be for enterprise customers, Android 14 enables this security feature in Android Enterprise, introducing support for IT admins to restrict the ability of a managed device to downgrade to 2G connectivity.
  • Added support to reject null-ciphered cellular connections, ensuring that circuit-switched voice and SMS traffic is always encrypted and protected from passive over-the-air interception. Learn more about Android's program to harden cellular connectivity.
  • Added support for multiple IMEIs
  • Since Android 14, AES-HCTR2 is the preferred mode of filenames encryption for devices with accelerated cryptography instructions.
  • Cellular connectivity
  • Documentation added for Android Safety Center
  • If your app targets Android 14 and uses Dynamic Code Loading (DCL), all dynamically-loaded files must be marked as read-only. Otherwise, the system throws an exception. We recommend that apps avoid dynamically loading code whenever possible, as doing so greatly increases the risk that an app can be compromised by code injection or code tampering.

Check out our full AOSP release notes and the Android Developer features and changes list.

Android 13

Every Android release includes dozens of security enhancements to protect users. Here are some of the major security enhancements available in Android 13:

  • Android 13 adds multi-document presentation support. This new Presentation Session interface enables an app to do a multi-document presentation, something which isn't possible with the existing API. For further information, refer to Identity Credential
  • In Android 13, intents originating from external apps are delivered to an exported component if and only if the intents match their declared intent-filter elements.
  • Open Mobile API (OMAPI) is a standard API used to communicate with a device's Secure Element. Before Android 13, only apps and framework modules had access to this interface. By converting it to a vendor stable interface, HAL modules are also capable of communicating with the secure elements through the OMAPI service. For more information, see OMAPI Vendor Stable Interface.
  • As of Android 13-QPR, shared UIDs are deprecated. Users of Android 13 or higher should put the line `android:sharedUserMaxSdkVersion="32"` in their manifest. This entry prevents new users from getting a shared UID. For further information on UIDs, see App signing.
  • Android 13 added support Keystore symmetric cryptographic primitives such as AES (Advanced Encryption Standard), HMAC (Keyed-Hash Message Authentication Code), and asymmetric cryptographic algorithms (including Elliptic Curve, RSA2048, RSA4096, and Curve 25519)
  • Android 13 (API level 33) and higher supports a runtime permission for sending non-exempt notifications from an app. This gives users control over which permission notifications they see.
  • Added per-use prompt for apps requesting access to all device logs, giving users the ability to allow or deny access.
  • introduced the Android Virtualization Framework (AVF), which brings together different hypervisors under one framework with standardized APIs. It provides secure and private execution environments for executing workloads isolated by hypervisor.
  • Introduced APK signature scheme v3.1 All new key rotations that use apksigner use the v3.1 signature scheme by default to target rotation for Android 13 and higher.

Check out our full AOSP release notes and the Android Developer features and changes list.

Android 12

Every Android release includes dozens of security enhancements to protect users. Here are some of the major security enhancements available in Android 12:

  • Android 12 introduces the BiometricManager.Strings API, which provides localized strings for apps that use BiometricPrompt for authentication. These strings are intended to be device-aware and provide more specificity about which authentication types might be used. Android 12 also includes support for under-display fingerprint sensors
  • Support added for under-display fingerprint sensors
  • Introduction of the Fingerprint Android Interface Definition Language (AIDL)
  • Support for new Face AIDL
  • Introduction of Rust as a language for platform development
  • The option for users to grant access only to their approximate location added
  • Added Privacy indicators on the status bar when an app is using the camera or microphone
  • Android's Private Compute Core (PCC)
  • Added an option to disable 2G support

Android 11

Every Android release includes dozens of security enhancements to protect users. For a list of some of the major security enhancements available in Android 11, see the Android Release Notes.

Android 10

Every Android release includes dozens of security enhancements to protect users. Android 10 includes several security and privacy enhancements. See the Android 10 release notes for a complete list of changes in Android 10.

Security

BoundsSanitizer

Android 10 deploys BoundsSanitizer (BoundSan) in Bluetooth and codecs. BoundSan uses UBSan's bounds sanitizer. This mitigation is enabled on a per-module level. It helps keep critical components of Android secure and shouldn't be disabled. BoundSan is enabled in the following codecs:

  • libFLAC
  • libavcdec
  • libavcenc
  • libhevcdec
  • libmpeg2
  • libopus
  • libvpx
  • libspeexresampler
  • libvorbisidec
  • libaac
  • libxaac

Execute-only memory

By default, executable code sections for AArch64 system binaries are marked execute-only (nonreadable) as a hardening mitigation against just-in-time code reuse attacks. Code that mixes data and code together and code that purposefully inspects these sections (without first remapping the memory segments as readable) no longer functions. Apps with a target SDK of Android 10 (API level 29 or higher) are impacted if the app attempts to read code sections of execute-only memory (XOM) enabled system libraries in memory without first marking the section as readable.

Extended access

Trust agents, the underlying mechanism used by tertiary authentication mechanisms such as Smart Lock, can only extend unlock in Android 10. Trust agents can no longer unlock a locked device and can only keep a device unlocked for a maximum of four hours.

Face authentication

Face authentication allows users to unlock their device simply by looking at the front of their device. Android 10 adds support for a new face authentication stack that can securely process camera frames, preserving security and privacy during face authentication on supported hardware. Android 10 also provides an easy way for security-compliant implementations to enable app integration for transactions such as online banking or other services.

Integer Overflow Sanitization

Android 10 enables Integer Overflow Sanitization (IntSan) in software codecs. Ensure that playback performance is acceptable for any codecs that aren't supported in the device's hardware. IntSan is enabled in the following codecs:

  • libFLAC
  • libavcdec
  • libavcenc
  • libhevcdec
  • libmpeg2
  • libopus
  • libvpx
  • libspeexresampler
  • libvorbisidec

Modular system components

Android 10 modularizes some Android system components and enables them to be updated outside of the normal Android release cycle. Some modules include:

OEMCrypto

Android 10 uses OEMCrypto API version 15.

Scudo

Scudo is a dynamic user-mode memory allocator designed to be more resilient against heap-related vulnerabilities. It provides the standard C allocation and deallocation primitives, as well as the C++ primitives.

ShadowCallStack

ShadowCallStack (SCS) is an LLVM instrumentation mode that protects against return address overwrites (like stack buffer overflows) by saving a function's return address to a separately allocated ShadowCallStack instance in the function prolog of nonleaf functions and loading the return address from the ShadowCallStack instance in the function epilog.

WPA3 and Wi-Fi Enhanced Open

Android 10 adds support for the Wi-Fi Protected Access 3 (WPA3) and Wi-Fi Enhanced Open security standards to provide better privacy and robustness against known attacks.

Privacy

App access when targeting Android 9 or lower

If your app runs on Android 10 or higher but targets Android 9 (API level 28) or lower, the platform applies the following behavior:

  • If your app declares a <uses-permission> element for either ACCESS_FINE_LOCATION or ACCESS_COARSE_LOCATION, the system automatically adds a <uses-permission> element for ACCESS_BACKGROUND_LOCATION during installation.
  • If your app requests either ACCESS_FINE_LOCATION or ACCESS_COARSE_LOCATION, the system automatically adds ACCESS_BACKGROUND_LOCATION to the request.

Background activity restrictions

Starting in Android 10, the system places restrictions on starting activities from the background. This behavior change helps minimize interruptions for the user and keeps the user more in control of what's shown on their screen. As long as your app starts activities as a direct result of user interaction, your app most likely isn't affected by these restrictions.
To learn more about the recommended alternative to starting activities from the background, see the guide on how to alert users of time-sensitive events in your app.

Camera metadata

Android 10 changes the breadth of information that the getCameraCharacteristics() method returns by default. In particular, your app must have the CAMERA permission in order to access potentially device-specific metadata that is included in this method's return value.
To learn more about these changes, see the section about camera fields that require permission.

Clipboard data

Unless your app is the default input method editor (IME) or is the app that currently has focus, your app cannot access clipboard data on Android 10 or higher.

Device location

To support the additional control that users have over an app's access to location information, Android 10 introduces the ACCESS_BACKGROUND_LOCATION permission.
Unlike the ACCESS_FINE_LOCATION and ACCESS_COARSE_LOCATION permissions, the ACCESS_BACKGROUND_LOCATION permission only affects an app's access to location when it runs in the background. An app is considered to be accessing location in the background unless one of the following conditions is satisfied:

  • An activity belonging to the app is visible.
  • The app is running a foreground service that has declared a foreground service type of location.
    To declare the foreground service type for a service in your app, set your app's targetSdkVersion or compileSdkVersion to 29 or higher. Learn more about how foreground services can continue user-initiated actions that require access to location.

External storage

By default, apps targeting Android 10 and higher are given scoped access into external storage, or scoped storage. Such apps can see the following types of files within an external storage device without needing to request any storage-related user permissions:

To learn more about scoped storage, as well as how to share, access, and modify files that are saved on external storage devices, see the guides on how to manage files in external storage and access and modify media files.

MAC address randomization

On devices that run Android 10 or higher, the system transmits randomized MAC addresses by default.
If your app handles an enterprise use case, the platform provides APIs for several operations related to MAC addresses:

  • Obtain randomized MAC address: Device owner apps and profile owner apps can retrieve the randomized MAC address assigned to a specific network by calling getRandomizedMacAddress().
  • Obtain actual, factory MAC address: Device owner apps can retrieve a device's actual hardware MAC address by calling getWifiMacAddress(). This method is useful for tracking fleets of devices.

Non-resettable device identifiers

Starting in Android 10, apps must have the READ_PRIVILEGED_PHONE_STATE privileged permission in order to access the device's non-resettable identifiers, which include both IMEI and serial number.

If your app doesn't have the permission and you try asking for information about non-resettable identifiers anyway, the platform's response varies based on target SDK version:

  • If your app targets Android 10 or higher, a SecurityException occurs.
  • If your app targets Android 9 (API level 28) or lower, the method returns null or placeholder data if the app has the READ_PHONE_STATE permission. Otherwise, a SecurityException occurs.

Physical activity recognition

Android 10 introduces the android.permission.ACTIVITY_RECOGNITION runtime permission for apps that need to detect the user's step count or classify the user's physical activity, such as walking, biking, or moving in a vehicle. This is designed to give users visibility of how device sensor data is used in Settings.
Some libraries within Google Play services, such as the Activity Recognition API and the Google Fit API, don't provide results unless the user has granted your app this permission.
The only built-in sensors on the device that require you to declare this permission are the step counter and step detector sensors.
If your app targets Android 9 (API level 28) or lower, the system auto-grants the android.permission.ACTIVITY_RECOGNITION permission to your app, as needed, if your app satisfies each of the following conditions:

  • The manifest file includes the com.google.android.gms.permission.ACTIVITY_RECOGNITION permission.
  • The manifest file doesn't include the android.permission.ACTIVITY_RECOGNITION permission.

If the system-auto grants the android.permission.ACTIVITY_RECOGNITION permission, your app retains the permission after you update your app to target Android 10. However, the user can revoke this permission at any time in system settings.

/proc/net filesystem restrictions

On devices that run Android 10 or higher, apps cannot access /proc/net, which includes information about a device's network state. Apps that need access to this information, such as VPNs, should use the NetworkStatsManager or ConnectivityManager class.

Permission groups removed from UI

As of Android 10, apps cannot look up how permissions are grouped in the UI.

Removal of contacts affinity

Starting in Android 10, the platform doesn't keep track of contacts affinity information. As a result, if your app conducts a search on the user's contacts, the results aren't ordered by frequency of interaction.
The guide about ContactsProvider contains a notice describing the specific fields and methods that are obsolete on all devices starting in Android 10.

Restricted access to screen contents

To protect users' screen contents, Android 10 prevents silent access to the device's screen contents by changing the scope of the READ_FRAME_BUFFER, CAPTURE_VIDEO_OUTPUT, and CAPTURE_SECURE_VIDEO_OUTPUT permissions. As of Android 10, these permissions are signature-access only.
Apps that need to access the device's screen contents should use the MediaProjection API, which displays a prompt asking the user to provide consent.

USB device serial number

If your app targets Android 10 or higher, your app cannot read the serial number until the user has granted your app permission to access the USB device or accessory.
To learn more about working with USB devices, see the guide on how to configure USB hosts.

Wi-Fi

Apps targeting Android 10 or higher cannot enable or disable Wi-Fi. The WifiManager.setWifiEnabled() method always returns false.
If you need to prompt users to enable and disable Wi-Fi, use a settings panel.

Restrictions on direct access to configured Wi-Fi networks

To protect user privacy, manual configuration of the list of Wi-Fi networks is restricted to system apps and device policy controllers (DPCs). A given DPC can be either the device owner or the profile owner.
If your app targets Android 10 or higher, and it isn't a system app or a DPC, then the following methods don't return useful data:

Android 9

Every Android release includes dozens of security enhancements to protect users. For a list of some of the major security enhancements available in Android 9, see the Android Release Notes.

Android 8

Every Android release includes dozens of security enhancements to protect users. Here are some of the major security enhancements available in Android 8.0:

  • Encryption. Added support to evict key in work profile.
  • Verified Boot. Added Android Verified Boot (AVB). Verified Boot codebase supporting rollback protection for use in boot loaders added to AOSP. Recommend bootloader support for rollback protection for the HLOS. Recommend boot loaders can only be unlocked by user physically interacting with the device.
  • Lock screen. Added support for using tamper-resistant hardware to verify lock screen credential.
  • KeyStore. Required key attestation for all devices that ship with Android 8.0+. Added ID attestation support to improve Zero Touch Enrollment.
  • Sandboxing. More tightly sandboxed many components using Project Treble's standard interface between framework and device-specific components. Applied seccomp filtering to all untrusted apps to reduce the kernel's attack surface. WebView is now run in an isolated process with very limited access to the rest of the system.
  • Kernel hardening. Implemented hardened usercopy, PAN emulation, read-only after init, and KASLR.
  • Userspace hardening. Implemented CFI for the media stack. App overlays can no longer cover system-critical windows and users have a way to dismiss them.
  • Streaming OS update. Enabled updates on devices that are are low on disk space.
  • Install unknown apps. Users must grant permission to install apps from a source that isn't a first-party app store.
  • Privacy. Android ID (SSAID) has a different value for each app and each user on the device. For web browser apps, Widevine Client ID returns a different value for each app package name and web origin. net.hostname is now empty and the dhcp client no longer sends a hostname. android.os.Build.SERIAL has been replaced with the Build.SERIAL API which is protected behind a user-controlled permission. Improved MAC address randomization in some chipsets.

Android 7

Every Android release includes dozens of security enhancements to protect users. Here are some of the major security enhancements available in Android 7.0:

  • File-based encryption. Encrypting at the file level, instead of encrypting the entire storage area as a single unit, better isolates and protects individual users and profiles (such as personal and work) on a device.
  • Direct Boot. Enabled by file-based encryption, Direct Boot allows certain apps such as alarm clock and accessibility features to run when device is powered on but not unlocked.
  • Verified Boot. Verified Boot is now strictly enforced to prevent compromised devices from booting; it supports error correction to improve reliability against non-malicious data corruption.
  • SELinux. Updated SELinux configuration and increased seccomp coverage further locks down the Application Sandbox and reduces attack surface.
  • Library load-order randomization and improved ASLR. Increased randomness makes some code-reuse attacks less reliable.
  • Kernel hardening. Added additional memory protection for newer kernels by marking portions of kernel memory as read-only, restricting kernel access to userspace addresses and further reducing the existing attack surface.
  • APK signature scheme v2. Introduced a whole-file signature scheme that improves verification speed and strengthens integrity guarantees.
  • Trusted CA store. To make it easier for apps to control access to their secure network traffic, user-installed certificate authorities and those installed through Device Admin APIs are no longer trusted by default for apps targeting API Level 24+. Additionally, all new Android devices must ship with the same trusted CA store.
  • Network Security Config. Configure network security and TLS through a declarative configuration file.

Android 6

Ogni release di Android include dozzine di miglioramenti della sicurezza per proteggere gli utenti. Ecco alcuni dei principali miglioramenti alla sicurezza disponibili in Android 6,0:

  • Autorizzazioni di runtime. Le app richiedono le autorizzazioni in fase di esecuzione anziché al momento dell'installazione. Gli utenti possono attivare e disattivare le autorizzazioni sia per la versione M sia per quella pre-M app.
  • Avvio verificato. Un insieme di controlli crittografici del sistema vengono condotti prima che per assicurare che lo smartphone sia integro dal bootloader tipo e quantità di spazio di archiviazione necessari e sistema operativo.
  • Sicurezza isolata dall'hardware. Nuovo livello di astrazione hardware (HAL) utilizzato dall'API Fingerprint, dalla schermata di blocco, dalla crittografia del dispositivo e dai certificati client per proteggere le chiavi da compromissione del kernel e/o attacchi fisici locali
  • Impronte. Ora i dispositivi possono essere sbloccati con un solo tocco. Gli sviluppatori possono inoltre sfruttare le nuove API per l'utilizzo delle fingerprint per bloccare e sbloccare le chiavi di crittografia.
  • Adesione alla scheda SD. I contenuti multimediali rimovibili possono essere adottato su un dispositivo ed espandere lo spazio di archiviazione disponibile per dati locali dell'app, foto, video e così via, ma essere comunque protetti dall'impostazione la crittografia.
  • Traffico di testo non cifrato. Gli sviluppatori possono utilizzare un nuovo StrictMode per assicurarsi che la loro app non utilizzi il testo non cifrato.
  • Rafforzamento del sistema. Rafforzamento del sistema tramite criteri applicato da SELinux. In questo modo viene offerto un migliore isolamento tra gli utenti, il filtro IOCTL, la riduzione della minaccia dei servizi esposti, un ulteriore rafforzamento dei domini SELinux e un accesso estremamente limitato a /proc.
  • Controllo dell'accesso USB: gli utenti devono confermare di consentire l'accesso USB a file, spazio di archiviazione o altre funzionalità sullo smartphone. Il valore predefinito ora è Solo addebito con accesso allo spazio di archiviazione che richiede l'approvazione esplicita dell'utente.

Android 5

5,0

Ogni release di Android include decine di miglioramenti della sicurezza per proteggere utenti. Ecco alcuni dei principali miglioramenti alla sicurezza disponibili in Android 5,0:

  • Criptati per impostazione predefinita. Sui dispositivi che vengono forniti con L La crittografia completa del disco pronta all'uso è abilitata per impostazione predefinita per migliorare Protezione dei dati su dispositivi smarriti o rubati. I dispositivi aggiornati a L possono essere criptati in Impostazioni > Sicurezza.
  • Crittografia completa del disco migliorata. La password utente è Protezione contro gli attacchi di forza bruta utilizzando scrypt e, dove se disponibile, la chiave è associata all'archivio chiavi hardware per impedire attacchi esterni al dispositivo. Come sempre, il segreto del blocco schermo di Android e la chiave di crittografia del dispositivo non vengono inviati dal dispositivo né esposti a nessuna applicazione.
  • Sandbox Android rafforzata con SELinux . Android adesso richiede SELinux in modalità di applicazione forzata per tutti i domini. SELinux è uno strumento di controllo dell'accesso obbligatorio (MAC) nel kernel Linux, utilizzato per aumentare l'attuale modello di sicurezza del controllo dell'accesso discrezionale (DAC). Questo nuovo livello fornisce protezione aggiuntiva contro potenziali vulnerabilità di sicurezza.
  • Smart Lock. Android ora include trustlet che offrono maggiore flessibilità per sbloccare i dispositivi. Ad esempio, i trustlet possono consentire di sbloccare automaticamente i dispositivi quando sono nelle vicinanze di un altro dispositivo attendibile (tramite NFC, Bluetooth) o quando vengono utilizzati da una persona con un volto attendibile.
  • Modalità multiutente, profilo con limitazioni e modalità ospite per smartphone e tablet. Android ora fornisce a più utenti di smartphone e include una modalità ospite che può essere utilizzata per fornire un accesso temporaneo e semplice ai tuoi dispositivo senza concedere l'accesso ai tuoi dati e alle tue app.
  • Aggiornamenti a WebView senza OTA. Ora WebView può essere aggiornati indipendentemente dal framework e senza sistema OTA. In questo modo è possibile rispondere più rapidamente a potenziali problemi di sicurezza in WebView.
  • Crittografia aggiornata per HTTPS e TLS/SSL. TLS 1.2 e TLS 1.1 sono ora attivati, la crittografia lato client è ora preferita, AES-GCM è ora attivato e le suite di crittografia deboli (MD5, 3DES e suite di crittografia di esportazione) sono ora disattivate. Per ulteriori dettagli, visita la pagina https://developer.android.com/reference/javax/net/ssl/SSLSocket.html.
  • supporto del linker non PIE rimosso. Android ora richiede eseguibili collegati dinamicamente per supportare PIE (eseguibili indipendenti dalla posizione). Questa funzionalità migliora lo spazio degli indirizzi di Android dell'implementazione di randomizzazione del layout (ASLR).
  • Miglioramenti a FORTIFY_SOURCE. Le seguenti funzioni libc ora implementano le protezioni FORTIFY_SOURCE: stpcpy(), stpncpy(), read(), recvfrom(), FD_CLR(), FD_SET() e FD_ISSET(). Questo fornisce protezione contro le vulnerabilità di corruzione della memoria queste funzioni.
  • Correzioni di sicurezza. Android 5.0 include anche correzioni per vulnerabilità specifiche di Android. Le informazioni su queste vulnerabilità hanno fornita ai membri di Open Handset Alliance e le correzioni sono disponibili in Progetto open source Android. Per migliorare la sicurezza, alcuni dispositivi con funzionalità di Android potrebbero includere anche queste correzioni.

Android 4 e versioni precedenti

Every Android release includes dozens of security enhancements to protect users. The following are some of the security enhancements available in Android 4.4:

  • Android sandbox reinforced with SELinux. Android now uses SELinux in enforcing mode. SELinux is a mandatory access control (MAC) system in the Linux kernel used to augment the existing discretionary access control (DAC) based security model. This provides additional protection against potential security vulnerabilities.
  • Per User VPN. On multi-user devices, VPNs are now applied per user. This can allow a user to route all network traffic through a VPN without affecting other users on the device.
  • ECDSA Provider support in AndroidKeyStore. Android now has a keystore provider that allows use of ECDSA and DSA algorithms.
  • Device Monitoring Warnings. Android provides users with a warning if any certificate has been added to the device certificate store that could allow monitoring of encrypted network traffic.
  • FORTIFY_SOURCE. Android now supports FORTIFY_SOURCE level 2, and all code is compiled with these protections. FORTIFY_SOURCE has been enhanced to work with clang.
  • Certificate Pinning. Android 4.4 detects and prevents the use of fraudulent Google certificates used in secure SSL/TLS communications.
  • Security Fixes. Android 4.4 also includes fixes for Android-specific vulnerabilities. Information about these vulnerabilities has been provided to Open Handset Alliance members and fixes are available in Android Open Source Project. To improve security, some devices with earlier versions of Android may also include these fixes.

Ogni release di Android include dozzine di miglioramenti della sicurezza per proteggere gli utenti. Di seguito sono riportati alcuni dei miglioramenti per la sicurezza disponibili in Android 4.3:

  • Sandbox Android rafforzata con SELinux. Questa release rafforza la sandbox di Android utilizzando SELinux un sistema di controllo dell'accesso obbligatorio (MAC) nel kernel Linux. Il rafforzamento di SELinux è invisibile a utenti e sviluppatori e aggiunge robustezza al modello di sicurezza Android esistente, mantenendo la compatibilità con le app esistenti. Per garantire la compatibilità, questa release consente l'utilizzo di SELinux in una modalità permissiva. Questa modalità registra tutti i criteri violazioni delle norme, ma senza interrompere le app né influire sul comportamento del sistema.
  • Nessun programma setuid o setgid. È stato aggiunto il supporto per le funzionalità del file system ai file di sistema di Android e sono stati rimossi tutti i programmi setuid o setgid. In questo modo si riduce la superficie di attacco del root e la probabilità di potenziali vulnerabilità di sicurezza.
  • Autenticazione ADB. A partire da Android 4.2.2, le connessioni ad ADB vengono autenticata con una coppia di chiavi RSA. In questo modo viene impedito l'uso non autorizzato di ADB se l'utente malintenzionato ha accesso fisico a un dispositivo.
  • Limita Setuid dalle app Android. La partizione /system è ora montata nosuid per i processi generati dagli zigote, impedendo le app per Android dall'esecuzione di programmi setuid. In questo modo si riducono la superficie di attacco la probabilità di potenziali vulnerabilità di sicurezza.
  • Limitazione delle funzionalità. Android zygote e ADB ora utilizzano prctl(PR_CAPBSET_DROP) per rilasciare di funzionalità non necessarie prima di eseguire le app. In questo modo, le app Android e le app avviate dalla shell non possono acquisire funzionalità con privilegi.
  • Provider AndroidKeyStore. Android ora dispone di un provider di archivi chiavi che consente alle app di creare chiavi di utilizzo esclusivo. In questo modo, le app con un'API per creare o archiviare chiavi private che non possono essere utilizzate altre app.
  • Portachiavi isBoundKeyAlgorithm. L'API Keychain ora fornisce un metodo (isBoundKeyType) che consente alle app di verificare che le chiavi di sistema siano associate a un'autorità di attendibilità hardware per il dispositivo. Ciò fornisce un luogo in cui creare o archiviare chiavi private che non possono essere esportate dispositivo, anche in caso di compromissione root.
  • NO_NEW_PRIVS Lo zigote Android ora utilizza prctl(PR_SET_NO_NEW_PRIVS) per bloccare l'aggiunta di nuovi privilegi prima dell'esecuzione del codice dell'app. In questo modo, le app Android non possono eseguire operazioni che possono elevare i privilegi tramite execve. (Richiede kernel Linux versione 3.5) o superiore).
  • FORTIFY_SOURCE miglioramenti. È stato attivato FORTIFY_SOURCE su Android x86 e MIPS e sono state rinforzate le chiamate strchr(), strrchr(), strlen() e umask(). Questo può rilevare potenziali vulnerabilità di corruzione della memoria o le costanti delle stringhe.
  • Protezioni per il trasferimento. Sono state attivate le riallocazioni di sola lettura (relro) per gli eseguibili collegati in modo statico e sono state rimosse tutte le riallocazioni di testo nel codice Android. In questo modo, viene garantita una difesa in profondità contro potenziali vulnerabilità legate alla corruzione della memoria.
  • EntropyMixer migliorato. EntropyMixer ora scrive l'entropia all'arresto o al riavvio, oltre alla miscelazione periodica. Ciò consente di conservare tutta l'entropia generata durante l'accensione dei dispositivi ed è particolarmente utile per i dispositivi che vengono riavviati immediatamente dopo il provisioning.
  • Correzioni relative alla sicurezza. Android 4.3 include anche correzioni per vulnerabilità specifiche di Android. Sono state fornite informazioni su queste vulnerabilità per i membri di Open Handset Alliance e le correzioni sono disponibili in Android Open Progetto di origine. Per migliorare la sicurezza, alcuni dispositivi con versioni precedenti di Android potrebbero includere anche queste correzioni.

Android provides a multi-layered security model described in the Android Security Overview. Each update to Android includes dozens of security enhancements to protect users. The following are some of the security enhancements introduced in Android 4.2:

  • App verification: Users can choose to enable Verify Apps and have apps screened by an app verifier, prior to installation. App verification can alert the user if they try to install an app that might be harmful; if an app is especially bad, it can block installation.
  • More control of premium SMS: Android provides a notification if an app attempts to send SMS to a short code that uses premium services that might cause additional charges. The user can choose whether to allow the app to send the message or block it.
  • Always-on VPN: VPN can be configured so that apps won't have access to the network until a VPN connection is established. This prevents apps from sending data across other networks.
  • Certificate pinning: The Android core libraries now support certificate pinning. Pinned domains receive a certificate validation failure if the certificate doesn't chain to a set of expected certificates. This protects against possible compromise of certificate authorities.
  • Improved display of Android permissions: Permissions are organized into groups that are more easily understood by users. During review of the permissions, the user can click on the permission to see more detailed information about the permission.
  • installd hardening: The installd daemon does not run as the root user, reducing potential attack surface for root privilege escalation.
  • init script hardening: init scripts now apply O_NOFOLLOW semantics to prevent symlink related attacks.
  • FORTIFY_SOURCE: Android now implements FORTIFY_SOURCE. This is used by system libraries and apps to prevent memory corruption.
  • ContentProvider default configuration: Apps that target API level 17 have export set to false by default for each Content Provider, reducing default attack surface for apps.
  • Cryptography: Modified the default implementations of SecureRandom and Cipher.RSA to use OpenSSL. Added SSL Socket support for TLSv1.1 and TLSv1.2 using OpenSSL 1.0.1
  • Security fixes: Upgraded open source libraries with security fixes include WebKit, libpng, OpenSSL, and LibXML. Android 4.2 also includes fixes for Android-specific vulnerabilities. Information about these vulnerabilities has been provided to Open Handset Alliance members and fixes are available in Android Open Source Project. To improve security, some devices with earlier versions of Android may also include these fixes.

Android fornisce un modello di sicurezza multilivello descritto nella Panoramica della sicurezza Android. Ogni aggiornamento di Android include decine di miglioramenti alla sicurezza per proteggere gli utenti. Ecco alcune delle funzionalità di sicurezza Miglioramenti introdotti nelle versioni di Android dalla 1.5 alla 4.1:

Android 1.5
  • ProPolice per evitare gli overrun del buffer dello stack (-fstack-protector)
  • safe_iop per ridurre i valori in eccesso degli interi
  • Estensioni a dlmalloc di OpenBSD per evitare vulnerabilità di doppio free() e per difendersi dagli attacchi di consolidamento dei chunk. Gli attacchi di consolidamento dei chunk sono un un modo comune per sfruttare il danneggiamento dell'heap.
  • Calloc OpenBSD per impedire gli overflow interi durante l'allocazione della memoria
Android 2.3
  • Protezioni per le vulnerabilità delle stringhe di formato (-Wformat-security -Werror=format-security)
  • No eXecute (NX) basato sull'hardware per impedire l'esecuzione di codice nello stack e nell'heap
  • Linux mmap_min_addr per mitigare il privilegio di rimozione del puntatore nullo Riassegnazione (migliorata ulteriormente in Android 4.1)
Android 4.0
ASLR (Address Space Layout Randomization) per randomizzare le posizioni delle chiavi in memoria
Android 4.1
  • Supporto di PIE (Position Independent Executable)
  • Trasferimenti di sola lettura / associazione immediata (-Wl,-z,relro -Wl,-z,now)
  • dmesg_restrict abilitato (evita la perdita degli indirizzi kernel)
  • kptr_restrict abilitato (evita la perdita degli indirizzi kernel)