CVE-2026-111061
mediumrussh is a Rust SSH client and server library that includes an SSH agent protocol implementation.
russh is a Rust SSH client and server library that includes an SSH agent protocol implementation. Prior to 0.64.1, the agent server spawns a separate long-lived task for every SSH_AGENT_CONSTRAIN_LIFETIME record in a constrained add-key request. The loop accepts repeated lifetime records, clones the key blob into each task, and does not roll back tasks when later constraint parsing fails. An attacker that can speak the agent protocol locally or through agent forwarding can exhaust memory and tasks until the agent process is starved or terminated, denying SSH agent service. This issue is fixed in version 0.64.1.
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L Affected products
Not reported by the source (unknown — not "none").
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
No vendor advisory or patch reference tagged by NVD. Check the references below.
References
- https://github.com/Eugeny/russh/commit/4c305033d72f8e5dd21a3fd4c53a6c291a16ebd1 security-advisories@github.com
- https://github.com/Eugeny/russh/releases/tag/v0.64.1 security-advisories@github.com
- https://github.com/Eugeny/russh/security/advisories/GHSA-4wc5-f2rc-q74m security-advisories@github.com
- https://github.com/Eugeny/russh/security/advisories/GHSA-4wc5-f2rc-q74m 134c704f-9b21-4f2e-91b3-4a467353bcc0