CVE-2026-56892 Overview
CVE-2026-56892 is a local information disclosure vulnerability in the ReadDataElement function of common.c, addressed in the Android Security Bulletin dated September 2026. An incorrect bounds check allows a local attacker to read data outside the intended buffer boundary. Exploitation requires no user interaction and no additional execution privileges, making it accessible to any local process on an affected device. The weakness is classified under [CWE-120] (Buffer Copy without Checking Size of Input). Successful exploitation exposes sensitive in-process memory content without altering system state.
Critical Impact
A local attacker can disclose sensitive memory contents from ReadDataElement without user interaction or elevated privileges.
Affected Products
- Android platform components referenced in the Android Security Bulletin September 2026
- Devices consuming the vulnerable common.cReadDataElement implementation
- Pixel devices covered by the September 2026 Pixel bulletin
Discovery Timeline
- 2026-09-15 - CVE-2026-56892 published to NVD
- 2026-09-16 - Last updated in NVD database
Technical Details for CVE-2026-56892
Vulnerability Analysis
The defect resides in ReadDataElement within common.c. The function performs an incorrect bounds check when reading a data element from an input buffer. Because the length or offset validation does not correctly constrain the read operation, the routine can access memory beyond the intended element boundary. The result is disclosure of adjacent memory contents to the caller. Confidentiality is impacted while integrity and availability remain unaffected, consistent with a read-only out-of-bounds condition.
Root Cause
The root cause is an improper boundary validation aligned with [CWE-120]. The bounds check in ReadDataElement fails to fully verify that the requested read stays within the allocated buffer. This class of defect commonly arises when signed and unsigned length values are compared, when arithmetic on offsets wraps or underflows, or when a computed end pointer is not re-validated against the buffer limit before dereference.
Attack Vector
Exploitation is local. An attacker with the ability to run code on the device, or to supply data to a component that invokes ReadDataElement, can trigger the flawed read path. No user interaction is required and no privileges are needed beyond what a normal process already holds. The attacker obtains disclosed bytes through the standard output or return channel of the affected component, which may contain sensitive material such as pointers, tokens, or process memory useful for defeating address space layout randomization.
No public proof-of-concept code has been published. See the Android Security Bulletin September 2026 for component-level detail.
Detection Methods for CVE-2026-56892
Indicators of Compromise
- Unexpected invocations of components that call ReadDataElement from unprivileged processes or apps
- Anomalous log entries or crashes referencing common.c parsing paths on unpatched builds
- Local processes reading structured data elements at rates or sizes inconsistent with normal application behavior
Detection Strategies
- Inventory devices against the September 2026 Android security patch level and flag any device below the fixed patch level
- Monitor for local applications requesting access to interfaces that ultimately invoke the vulnerable parsing routine
- Correlate crash telemetry and abnormal termination signals from components handling the affected data format
Monitoring Recommendations
- Ingest mobile device management (MDM) posture data to track Android security patch level compliance across the fleet
- Alert on installation of untrusted local applications on devices that have not yet received the September 2026 patch
- Review vendor bulletins for updates to the affected component list and adjust detection scope accordingly
How to Mitigate CVE-2026-56892
Immediate Actions Required
- Apply the September 2026 Android security patch level, or later, to all managed devices
- Prioritize patching for devices that permit sideloading or that run untrusted local applications
- Restrict installation of unknown applications through MDM policy until patches are deployed
Patch Information
The fix is delivered as part of the Android Security Bulletin dated September 2026. Refer to the Android Security Bulletin September 2026 for the affected component list, patch identifiers, and device-specific patch level guidance. Devices reporting a security patch level of 2026-09-01 or later include the corrected bounds check in ReadDataElement.
Workarounds
- Limit local attack surface by removing untrusted third-party applications from affected devices
- Enforce Google Play Protect and disable installation from unknown sources through MDM configuration
- Segment devices that cannot be patched immediately from sensitive network resources
# Verify Android security patch level on a device via adb
adb shell getprop ro.build.version.security_patch
# Expected value: 2026-09-01 or later
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.