OSV-2020-1851 Stack-buffer-underflow in fmt::v6::basic_format_args<fmt::v6::basic_format_context<std::__1::back_insert_i
Not scored
Published
Check this codebase for OSV-2020-1851 and fix it if it is affected.
What it is: OSV-2020-1851 is a memory corruption vulnerability in libfmt, published on 26 Sep 2020.
Exploitation: There is no known exploitation of OSV-2020-1851 in the wild and no public exploit code.
Affected packages and fixed versions:
- libfmt (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-2020-1851/ (Markdown: https://insights.sbomify.com/OSV-2020-1851/index.md)
A stack-buffer-underflow in the fmt library can cause a crash, potentially leading to denial of service for applications using it.
- Exploited in the wild
- Not known
- Login needed
- Not stated
- Attackable
- Not stated
- Victim action needed
- Not stated
- Fix
- None listed
What is OSV-2020-1851?
OSV-2020-1851 is a memory corruption vulnerability in libfmt, published on 26 Sep 2020.
Official description
OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=21794
Crash type: Stack-buffer-underflow READ 16
Crash state:
fmt::v6::basic_format_args<fmt::v6::basic_format_context<std::__1::back_insert_i
fmt::v6::basic_format_args<fmt::v6::basic_format_context<std::__1::back_insert_i
fmt::v6::basic_format_context<std::__1::back_insert_iterator<fmt::v6::internal::
Which versions are affected by OSV-2020-1851?
1 open source package ship an affected version, including libfmt.
| Package | Affected | Fixed in |
|---|---|---|
libfmt OSS-Fuzz | All versions | None |
How do I fix OSV-2020-1851?
No fix has been published for OSV-2020-1851 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is OSV-2020-1851 being exploited?
There is no known exploitation of OSV-2020-1851 in the wild and no public exploit code.