| Name | CVE-2025-8277 |
| Description | A flaw was found in libssh's handling of key exchange (KEX) processes when a client repeatedly sends incorrect KEX guesses. The library fails to free memory during these rekey operations, which can gradually exhaust system memory. This issue can lead to crashes on the client side, particularly when using libgcrypt, which impacts application stability and availability. |
| Source | CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
| Debian Bugs | 1114859 |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| libssh (PTS) | bullseye (security), bullseye | 0.9.8-0+deb11u1 | vulnerable |
| bookworm, bookworm (security) | 0.10.6-0+deb12u1 | vulnerable | |
| trixie | 0.11.2-1 | vulnerable | |
| forky, sid | 0.11.3-1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| libssh | source | (unstable) | 0.11.3-1 | 1114859 |
[trixie] - libssh <no-dsa> (Minor issue)
[bookworm] - libssh <no-dsa> (Minor issue)
[bullseye] - libssh <no-dsa> (Minor issue)
https://bugzilla.redhat.com/show_bug.cgi?id=2383888
https://www.libssh.org/security/advisories/CVE-2025-8277.txt
https://git.libssh.org/projects/libssh.git/commit/?id=ffed80f8c078122990a4eba2b275facd56dd43e0
https://git.libssh.org/projects/libssh.git/commit/?id=c9d95ab0c7a52b231bcec09afbea71944ed0d852
https://git.libssh.org/projects/libssh.git/commit/?id=ccff22d3787c1355b3f0dcd09fe54d90acc55bf1
https://git.libssh.org/projects/libssh.git/commit/?id=4310a696f2d632c6742678077d703d9b9ff3bc0e
https://git.libssh.org/projects/libssh.git/commit/?h=stable-0.11&id=87db2659ec608a977a63eea529f17b9168388d73 (libssh-0.11.3)
https://git.libssh.org/projects/libssh.git/commit/?h=stable-0.11&id=266174a6d36687b65cf90174f06af90b8b27c65f (libssh-0.11.3)
https://git.libssh.org/projects/libssh.git/commit/?h=stable-0.11&id=8e4d67aa9eda455bfad9ac610e54b7a548d0aa08 (libssh-0.11.3)
https://git.libssh.org/projects/libssh.git/commit/?h=stable-0.11&id=1c763e29d138db87665e98983f468d2dd0f286c1 (libssh-0.11.3)