CVE-2025-8277
Published: September 10, 2025Last modified: September 26, 2025
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.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 3.1 |
| Attack Vector | NETWORK |
| Attack complexity | HIGH |
| Privileges required | LOW |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | NONE |
| Integrity impact | NONE |
| Availability impact | LOW |
| Vector | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L |
Notes
https://www.libssh.org/security/advisories/CVE-2025-8277.txt Fixed in 0.11.3
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | libssh | Fixed (0.11.3-r0) |
| 25 LTS | libssh | Fixed (0.11.3-r0) | |
| Stream | libssh | Fixed (0.11.3-r0) |