CVE-2026-116696lowCWE-770

CVE-2026-116696: low-severity vulnerability in Eugeny russh

russh's SSH agent server is susceptible to unbound allocations via repeated SSH_AGENT_CONSTRAIN_CONFIRM messages

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8Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 3.3epss 0.1%
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.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
Affected products
Eugeny · russh
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