CVE-2021-0696
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedIn dllist_remove_node of TBD, there is a possible use after free bug due to a race condition. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android SoCAndroid ID: A-242344778
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceA race condition in dllist_remove_node leads to use-after-free in Android SoC components. The doubly-linked list removal function does not properly synchronize, allowing a node to be freed while still referenced, which can be exploited for local privilege escalation.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE dataall versionsCVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Local
- Complexity
- High
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Identify the Android versionRun 'getprop ro.build.version.release' or check Settings > About Phone > Android versionAffected if The device runs any version of Android, as all versions are affected according to the CVE
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Identify the kernel versionRun 'uname -r' or 'cat /proc/version'Affected if The kernel version is any version, as the vulnerability exists in the underlying SoC component code
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Determine the SoC/chipset vendorRun 'getprop ro.board.platform' or 'getprop ro.hardware' to identify the System-on-Chip providerAffected if The device uses any SoC that includes the vulnerable dllist_remove_node implementation in its kernel components
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Check for the vulnerable dllist code pathSearch the kernel or driver binaries for symbols related to 'dllist_remove_node' or 'dllist' using 'grep -r dllist_remove_node /system/lib/modules/' or similar paths on the deviceAffected if The device contains the vulnerable dllist removal function in its kernel or driver code
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Verify if kernel debugging or tracing is enabledCheck /proc/sys/kernel/ftrace_enabled or verify if kernel debug options are active; the race condition requires the vulnerable code path to be executable in the kernelAffected if The kernel is running with the vulnerable dllist code present and accessible
The device is affected if it runs any version of Android and contains the vulnerable dllist_remove_node implementation in its SoC kernel components, regardless of specific version numbers.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
From vendor dataApply the vendor-specific security patch from the SoC manufacturer; this is a kernel-level race condition requiring proper synchronization primitives in the list removal code.
- Consultation3.0 h
- Implementation6.0 h
- Testing4.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,224.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-0696 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2021-0696 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
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