CVE-2025-26466
5.9
MEDIUM
CVSS 3.1
EPSS 62.4%
Description
A flaw was found in the OpenSSH package. For each ping packet the SSH server receives, a pong packet is allocated in a memory buffer and stored in a queue of packages. It is only freed when the server/client key exchange has finished. A malicious client may keep sending such packages, leading to an uncontrolled increase in memory consumption on the server side. Consequently, the server may become unavailable, resulting in a denial of service attack.
How to fix CVE-2025-26466
To remediate CVE-2025-26466, upgrade the affected package to a fixed version below.
- —upgrade to 9.6_p1-r2 or later
- —upgrade to 1:9.9p2-1 or later
Is CVE-2025-26466 being exploited?
Likely — EPSS is 62.4%, placing CVE-2025-26466 in the top tier of vulnerabilities by exploitation probability. Prioritise patching.
Affected packages (2)
- from 0, < 9.6_p1-r2
- from 0, < 1:9.9p2-1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H |