{"id":"CVE-2026-116794","state":"PUBLISHED","title":"russh: Agent server never calls `Agent::confirm`, so keys added with the confirm constraint (`ssh-add -c`) sign without confirmation","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.","publishedAt":"2026-10-28T17:06:57.542Z","updatedAt":"2026-10-28T17:06:57.542Z","severity":{"score":8.3,"label":"High","version":"4.0","vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:H/SI:H/SA:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["Eugeny russh"],"affected":[{"vendor":"Eugeny","product":"russh","versions":[{"version":"< 0.65","status":"affected"}]}],"references":["https://github.com/Eugeny/russh/security/advisories/GHSA-vp5q-ff62-jwqv","https://github.com/Eugeny/russh/commit/3e04597dc54e36bfc85c21996f7d8d9d224e9826","https://github.com/Eugeny/russh/commit/62db6e7defd6d244159da962ccccb029e785ce0f","https://github.com/Eugeny/russh/releases/tag/v0.65.0"],"weaknesses":["CWE-862"],"ingestedAt":"2026-10-29T20:10:43.281Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/116xxx/CVE-2026-116794.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-116794","state":"PUBLISHED","datePublished":"2026-10-28T17:06:57.542Z","dateUpdated":"2026-10-28T17:06:57.542Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-10-26T21:53:35.168Z"},"containers":{"cna":{"title":"russh: Agent server never calls `Agent::confirm`, so keys added with the confirm constraint (`ssh-add -c`) sign without confirmation","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"Eugeny","product":"russh","versions":[{"version":"< 0.65","status":"affected"}]}],"references":[{"url":"https://github.com/Eugeny/russh/security/advisories/GHSA-vp5q-ff62-jwqv","name":"https://github.com/Eugeny/russh/security/advisories/GHSA-vp5q-ff62-jwqv","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/Eugeny/russh/commit/3e04597dc54e36bfc85c21996f7d8d9d224e9826","name":"https://github.com/Eugeny/russh/commit/3e04597dc54e36bfc85c21996f7d8d9d224e9826","tags":["x_refsource_MISC"]},{"url":"https://github.com/Eugeny/russh/commit/62db6e7defd6d244159da962ccccb029e785ce0f","name":"https://github.com/Eugeny/russh/commit/62db6e7defd6d244159da962ccccb029e785ce0f","tags":["x_refsource_MISC"]},{"url":"https://github.com/Eugeny/russh/releases/tag/v0.65.0","name":"https://github.com/Eugeny/russh/releases/tag/v0.65.0","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV4_0":{"attackVector":"LOCAL","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"LOW","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"HIGH","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"HIGH","subIntegrityImpact":"HIGH","subAvailabilityImpact":"NONE","baseScore":8.3,"baseSeverity":"HIGH","vectorString":"CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:H/SI:H/SA:N","version":"4.0"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-862","lang":"en","description":"CWE-862: Missing Authorization","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-10-28T17:06:57.542Z"},"source":{"advisory":"GHSA-vp5q-ff62-jwqv","discovery":"UNKNOWN"}}}}}