Rust russh: From 0.50.0-beta.12 until 0.65.0, the agent server's Connection::try_sign path in
Affects rust-russhSource GCVE Database
Not known to be exploited · CVSS 8.3 High · fixed in 0.65.0 : patch rust-russh soon.
Data as of 5 Nov 2026, 12:35 UTC
Thin evidence
One scorer or none| CNA (GitHub_M) | CVSS 4.0 | 8.3 |
|---|
- Patch
- Available – fixed in 0.65.0
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:H/SI:H/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 28 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 5 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.10rust-russhpkg:deb/ubuntu/rust-russh?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
russh is a Rust SSH client and server library that includes an SSH agent protocol implementation. From 0.50.0-beta.12 until 0.65.0, the agent server's Connection::try_sign path in russh/src/keys/agent/server.rs recognizes SSH_AGENT_CONSTRAIN_CONFIRM but returns a hard-coded successful result instead of calling Agent::confirm. In applications that override Agent::confirm to require user approval or another policy check, a process that can reach the agent socket, including the remote side of a forwarded agent, can use a key added through ssh-add -c without that check and can authenticate or sign data as the user while the key remains loaded. The separate Agent::confirm_request hook still runs for every signing request, so checks implemented there remain effective, and implementations that retain the default always-successful Agent::confirm do not lose an approval check through this regression. This issue is fixed in version 0.65.0.
References
- ubuntu.com/security/CVE-2026-116794 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-116794 (opens in a new tab)
- github.com/Eugeny/russh/security/advisories/GHSA-vp5q-ff62-jwqv (opens in a new tab)
- github.com/Eugeny/russh/commit/3e04597dc54e36bfc85c21996f7d8d9d224e9826 (opens in a new tab)
- github.com/Eugeny/russh/commit/62db6e7defd6d244159da962ccccb029e785ce0f (opens in a new tab)
- github.com/Eugeny/russh/releases/tag/v0.65.0 (opens in a new tab)