OSV-2025-92 Null-dereference READ in session_startup
Not scored
Published
Check this codebase for OSV-2025-92 and fix it if it is affected.
What it is: OSV-2025-92 is a vulnerability in libssh2, published on 5 Feb 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of OSV-2025-92 in the wild and no public exploit code.
Affected packages and fixed versions:
- libssh2 (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-2025-92/ (Markdown: https://insights.sbomify.com/OSV-2025-92/index.md)
A null pointer dereference in libssh2's session startup can cause a denial of service during the SSH handshake.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is OSV-2025-92?
OSV-2025-92 is a vulnerability in libssh2, published on 5 Feb 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=393523566
Crash type: Null-dereference READ
Crash state:
session_startup
libssh2_session_handshake
ssh2_client_fuzzer.cc
Which versions are affected by OSV-2025-92?
1 open source package ship an affected version, including libssh2.
| Package | Affected | Fixed in |
|---|---|---|
libssh2 OSS-Fuzz | All versions | None |
How do I fix OSV-2025-92?
No fix has been published for OSV-2025-92 yet. Limit exposure of the affected software until one is available.
Is OSV-2025-92 being exploited?
There is no known exploitation of OSV-2025-92 in the wild and no public exploit code.