{"id":"UBUNTU-CVE-2026-102822","details":"Russh is a Rust SSH client and server library. Prior to 0.63.1, a connection configured to permit mac=none can negotiate it with a MAC-requiring CTR or CBC block cipher because the selection logic validates needs_mac() only when MAC selection fails. A remote peer can then send a packet with a decrypted length of zero, causing russh/src/cipher/mod.rs to shrink the previously read block before indexing buffer.buffer[16..], which panics and terminates the connection task. This issue is fixed in version 0.63.1.","modified":"2026-10-17T12:57:57.036658244Z","published":"2026-09-29T19:17:00Z","upstream":["CVE-2026-102822"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-102822"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-102822"},{"type":"REPORT","url":"https://github.com/Eugeny/russh/security/advisories/GHSA-p8qx-h547-fjw9"},{"type":"REPORT","url":"https://github.com/Eugeny/russh/commit/2885385abfee279092a41d80c6cb6ac367353159"},{"type":"REPORT","url":"https://github.com/Eugeny/russh/releases/tag/v0.63.1"}],"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-2026-102822.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L"},{"type":"Ubuntu","score":"medium"}]}