{"id":"UBUNTU-CVE-2026-111062","details":"russh is a Rust SSH client and server library. From version 0.34.0-beta.1 until version 0.64.0, its SSH server does not require the signature algorithm in a public-key authentication signature to match the algorithm named in the authentication request. A client possessing an authorized RSA private key can announce  rsa-sha2-512  while supplying a valid  ssh-rsa SHA-1 signature, bypassing restrictions or producing misleading audit records when applications rely on the requested algorithm. A valid private-key signature remains required, and russh clients are not affected. This issue is fixed in version 0.64.0.","modified":"2026-11-07T01:45:11.932499756Z","published":"2026-11-06T00:00:00Z","upstream":["CVE-2026-111062"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-111062"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-111062"},{"type":"REPORT","url":"https://github.com/Eugeny/russh/commit/a0ded76bdc352f8fbeaaeb175fb2a0c586fbc8f2"},{"type":"REPORT","url":"https://github.com/Eugeny/russh/pull/759"},{"type":"REPORT","url":"https://github.com/Eugeny/russh/releases/tag/v0.64.0"},{"type":"REPORT","url":"https://github.com/Eugeny/russh/security/advisories/GHSA-j7h2-66j4-ghjf"}],"affected":[{"package":{"name":"rust-russh","ecosystem":"Ubuntu:26.10","purl":"pkg:deb/ubuntu/rust-russh?arch=source&distro=stonking"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.57.1-2"],"ecosystem_specific":{"binaries":[{"binary_name":"librust-russh-dev","binary_version":"0.57.1-2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-111062.json"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N"},{"type":"Ubuntu","score":"medium"}]}