CVE-2026-58835 Overview
CVE-2026-58835 is a heap buffer overflow [CWE-122] in the cfg2prop function of btif_storage.cc, a Bluetooth component in Google Android. The flaw allows an out-of-bounds write that can lead to remote code execution. Exploitation requires no user interaction and no additional execution privileges beyond those already granted to the Bluetooth stack. Google addressed the issue in the October 2026 Android Security Bulletin. Affected releases include Android 16.0 (including QPR2 Beta 1, 2, and 3) and Android 17.0.
Critical Impact
An attacker within Bluetooth range can trigger memory corruption in the Bluetooth stack and achieve remote code execution without user interaction.
Affected Products
- Google Android 16.0 (stable release)
- Google Android 16.0 QPR2 Beta 1, Beta 2, and Beta 3
- Google Android 17.0
Discovery Timeline
- 2026-10-01 - Google releases fix in the Android Security Bulletin
- 2026-10-05 - CVE-2026-58835 published to NVD
- 2026-10-07 - Last updated in NVD database
Technical Details for CVE-2026-58835
Vulnerability Analysis
The vulnerability resides in the cfg2prop routine within btif_storage.cc, part of the Bluetooth Interface (BTIF) layer in Android's Bluetooth stack. The function translates configuration entries into Bluetooth properties stored on the heap. Insufficient validation of input length or element count permits a write past the bounds of a heap-allocated buffer. An attacker who can influence the stored Bluetooth configuration data, for example through a crafted peer device interaction, can corrupt adjacent heap metadata or objects. Successful exploitation yields code execution within the Bluetooth process, which holds sensitive system privileges on Android devices.
Root Cause
The root cause is a classic heap-based buffer overflow categorized under [CWE-122]. The cfg2prop function copies configuration-derived data into a heap buffer without correctly bounding the write size against the allocated capacity. When attacker-controlled configuration content exceeds expected limits, the write proceeds past the buffer boundary and overwrites neighboring heap memory.
Attack Vector
The attack vector is network-adjacent via Bluetooth. The CVSS vector indicates low privileges are required on the target, and no user interaction is needed. A paired or pairing peer device can supply malformed data that is persisted into the Bluetooth configuration store and later parsed by cfg2prop. The resulting corruption can be leveraged for remote code execution in the Bluetooth process context, which commonly runs with elevated permissions and access to radio, media, and personal data interfaces.
No public proof-of-concept exploit is listed for this issue. Technical specifics of the fix are documented in the Android Security Bulletin October 2026.
Detection Methods for CVE-2026-58835
Indicators of Compromise
- Unexpected crashes or restarts of the com.android.bluetooth process, particularly reproducible after specific peer interactions.
- Tombstone or logcat entries referencing btif_storage, cfg2prop, or heap corruption signatures such as SIGSEGV in the Bluetooth process.
- Repeated pairing attempts from unknown Bluetooth devices in proximity to targeted hosts.
Detection Strategies
- Monitor Android device logs for abnormal Bluetooth stack termination patterns and native crash reports originating in BTIF components.
- Correlate Bluetooth pairing or connection events with subsequent process crashes to identify potential exploitation attempts.
- Review mobile device management (MDM) telemetry for devices running Android 16.0 or 17.0 that have not received the October 2026 security patch level.
Monitoring Recommendations
- Ingest Android crash and security logs into a centralized analytics platform to flag Bluetooth-related anomalies at scale.
- Track patch level compliance across the mobile fleet and alert on devices still exposed to the October 2026 Android bulletin issues.
- Monitor physical and corporate environments for unexpected Bluetooth broadcasts in sensitive areas where device compromise would be impactful.
How to Mitigate CVE-2026-58835
Immediate Actions Required
- Apply the October 2026 Android security patch (2026-10-01 security patch level or later) to all affected devices.
- Disable Bluetooth on devices that cannot be immediately patched, particularly in high-risk or public environments.
- Audit paired Bluetooth devices and remove any unknown or untrusted pairings.
Patch Information
Google released the fix in the Android Security Bulletin October 2026. Device manufacturers (OEMs) distribute the patch as part of monthly over-the-air updates. Confirm the security patch level under device Settings and ensure it reflects 2026-10-01 or later.
Workarounds
- Keep Bluetooth turned off when not actively in use to eliminate the network-adjacent attack surface.
- Enforce Bluetooth restrictions through MDM policies on managed devices awaiting the vendor patch.
- Avoid pairing with untrusted or unknown Bluetooth peripherals until patched firmware is deployed across the fleet.
# Verify Android security patch level via adb
adb shell getprop ro.build.version.security_patch
# Expected output on patched devices: 2026-10-01 or later
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.