{"id":"MGASA-2021-0441","summary":"Updated libssh packages fix security vulnerability","details":"A flaw has been found in libssh in versions prior to 0.9.6. The SSH\nprotocol keeps track of two shared secrets during the lifetime of the\nsession. One of them is called secret_hash and the other session_id.\nInitially, both of them are the same, but after key re-exchange, previous\nsession_id is kept and used as an input to new secret_hash. Historically,\nboth of these buffers had shared length variable, which worked as long as\nthese buffers were same. But the key re-exchange operation can also change\nthe key exchange method, which can be based on hash of different size,\neventually creating \"secret_hash\" of different size than the session_id\nhas. This becomes an issue when the session_id memory is zeroed or when it\nis used again during second key re-exchange. (CVE-2021-3634)\n","modified":"2026-02-04T02:22:23.158704Z","published":"2021-09-23T04:49:29Z","related":["CVE-2021-3634"],"references":[{"type":"ADVISORY","url":"https://advisories.mageia.org/MGASA-2021-0441.html"},{"type":"REPORT","url":"https://bugs.mageia.org/show_bug.cgi?id=29419"},{"type":"REPORT","url":"https://www.libssh.org/security/advisories/CVE-2021-3634.txt"},{"type":"REPORT","url":"https://www.libssh.org/2021/08/26/libssh-0-9-6-security-release/"},{"type":"REPORT","url":"https://ubuntu.com/security/notices/USN-5053-1"},{"type":"REPORT","url":"https://www.debian.org/security/2021/dsa-4965"}],"affected":[{"package":{"name":"libssh","ecosystem":"Mageia:8","purl":"pkg:rpm/mageia/libssh?arch=source&distro=mageia-8"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.9.6-1.mga8"}]}],"ecosystem_specific":{"section":"core"},"database_specific":{"source":"https://advisories.mageia.org/MGASA-2021-0441.json"}}],"schema_version":"1.7.3","credits":[{"name":"Mageia","contact":["https://wiki.mageia.org/en/Packages_Security_Team"],"type":"COORDINATOR"}]}