OSV-2021-777 Heap-use-after-free in xmlAddNextSibling
Not scored
Published
Check this codebase for OSV-2021-777 and fix it if it is affected.
What it is: OSV-2021-777 is an use after free vulnerability in libxml2, published on 20 May 2021.
Exploitation: There is no known exploitation of OSV-2021-777 in the wild and no public exploit code.
Affected packages and fixed versions:
- libxml2 (OSS-Fuzz): affected all versions; no fix listed
Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.
Reference: https://insights.sbomify.com/OSV-2021-777/ (Markdown: https://insights.sbomify.com/OSV-2021-777/index.md)
A heap-use-after-free vulnerability in the XML parsing library allows attackers to cause denial of service or potentially execute code via crafted XML input.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Not stated
- Victim action needed
- Not needed
- Fix
- None listed
What is OSV-2021-777?
OSV-2021-777 is an use after free vulnerability in libxml2, published on 20 May 2021.
Official description
OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=34461
Crash type: Heap-use-after-free READ 4
Crash state:
xmlAddNextSibling
xmlXIncludeCopyRange
xmlXIncludeCopyXPointer
Which versions are affected by OSV-2021-777?
1 open source package ship an affected version, including libxml2.
| Package | Affected | Fixed in |
|---|---|---|
libxml2 OSS-Fuzz | All versions | None |
How do I fix OSV-2021-777?
No fix has been published for OSV-2021-777 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is OSV-2021-777 being exploited?
There is no known exploitation of OSV-2021-777 in the wild and no public exploit code.