CVE-2026-116696 russh's SSH agent server is susceptible to unbound allocations via repeated SSH_AGENT_CONSTRAIN_CONFIRM messages
- Exploited in the wild
- Not known
- Fix
- None listed
What is CVE-2026-116696?
CVE-2026-116696 is a low-severity vulnerability in Eugeny russh, published on 27 Oct 2026.
Official description
russh is a Rust SSH client and server library that includes an SSH agent protocol implementation. Prior to 0.65.0, russh::keys::agent::server::serve in russh/src/keys/agent/server.rs accepts repeated SSH_AGENT_CONSTRAIN_CONFIRM records while adding a key and appends every Constraint::Confirm record to the key's retained constraint vector without a count or memory limit. A process that can connect to the agent socket, including the remote side of a forwarded agent session, can repeatedly add constrained keys and cause renewable memory growth that persists for the process lifetime because keys without a lifetime constraint do not expire. This issue is fixed in version 0.65.0.
Weakness: CWE-770
Which versions are affected by CVE-2026-116696?
How do I fix CVE-2026-116696?
No fix has been published for CVE-2026-116696 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-116696 being exploited?
There is no known exploitation of CVE-2026-116696 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-116696, GHSA-9wfm-jcj8-jfv9, UBUNTU-CVE-2026-116696.