CVE-2026-0039
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 multiple functions of ubsan_throwing_runtime.cpp, there is a possible persistent denial of service due to an integer overflow. This could lead to remote denial of service with no additional execution privileges needed. User interaction is not needed for exploitation.
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 · moderate confidenceAn integer overflow vulnerability exists in multiple functions within the UBSan (Undefined Behavior Sanitizer) runtime library file ubsan_throwing_runtime.cpp. This compiler runtime component, used during development for detecting undefined behavior, contains integer overflow conditions that can cause a persistent denial of service when instrumented applications encounter the overflow during runtime checks. No user interaction or elevated privileges are required for exploitation.
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 data= 14.0= 15.0= 16.0CVSS 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
- Network
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/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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Check Android OS versionRun 'getprop ro.build.version.release' or check Settings > About Phone > Android versionAffected if The device runs Android 14.0, 15.0, or 16.0 specifically (exact version match)
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Identify if UBSan is linked in the target binaryUse 'objdump -p BINARY | grep -i ubsan' or check for strings like 'ubsan' in the binary, or examine the .dynamic section for UBSan runtime library referencesAffected if The binary links against libubsan.so or contains UBSan runtime instrumentation
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Check for UBSan runtime library presence on the systemSearch for libubsan.so on the device: 'find / -name "libubsan*" 2>/dev/null' or check /system/lib64/ and /system/lib/Affected if The libubsan.so library is present on the system and gets loaded by any process
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Inspect build configuration for sanitizer flagsReview the Makefile, CMakeLists.txt, or build.gradle for flags such as -fsanitize=undefined or -fsanitize=undefined,integer and verify if UBSan is enabled in the final buildAffected if Build configuration contains '-fsanitize=undefined' or similar UBSan flags that compile in the runtime
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Verify if this is a production build with sanitizer enabledCheck whether the binary is a debug/release build with sanitizer instrumentation: 'file BINARY' and look for debug symbols, or use 'readelf -d BINARY | grep -i sanitize'Affected if The binary is a production release that still contains UBSan instrumentation (sanitizers should only be in debug/dev builds)
A user is affected if their Android device runs version 14.0, 15.0, or 16.0 AND the target application or system binary includes UBSan runtime instrumentation (libubsan) that gets loaded into memory.
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 dataUpdate the LLVM/Clang toolchain to the latest version containing the patch for this vulnerability, or remove UBSan instrumentation from production builds if toolchain update is not feasible.
- Consultation2.0 h
- Implementation2.0 h
- Testing2.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,984.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-0039 — 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-2026-0039 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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- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
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