OSV-2021-495 Heap-double-free in bit_chain_free
Not scored
Published
Check this codebase for OSV-2021-495 and fix it if it is affected.
What it is: OSV-2021-495 is an use after free vulnerability in libredwg, published on 6 Mar 2021.
Exploitation: There is no known exploitation of OSV-2021-495 in the wild and no public exploit code.
Affected packages and fixed versions:
- libredwg (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-2021-495/ (Markdown: https://insights.sbomify.com/OSV-2021-495/index.md)
A heap double-free vulnerability in the DWG encoding library allows attackers to cause denial of service or potentially execute code via crafted files.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Not stated
- Victim action needed
- Not needed
- Fix
- None listed
What is OSV-2021-495?
OSV-2021-495 is an use after free vulnerability in libredwg, published on 6 Mar 2021.
Official description
OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=31724
Crash type: Heap-double-free
Crash state:
bit_chain_free
dwg_encode_MTEXT
dwg_encode_add_object
Which versions are affected by OSV-2021-495?
1 open source package ship an affected version, including libredwg.
| Package | Affected | Fixed in |
|---|---|---|
libredwg OSS-Fuzz | All versions | None |
How do I fix OSV-2021-495?
No fix has been published for OSV-2021-495 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-2021-495 being exploited?
There is no known exploitation of OSV-2021-495 in the wild and no public exploit code.