CVE-2025-26466
MEDIUM EPSS 98.4%
Published Feb 28, 20251y ago · Modified Jun 17, 20261w ago
5.9 CVSS 3.1
Published Feb 28, 2025 1y ago
Last Modified Jun 17, 2026 1w ago
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.
CVSS Details
Base Score
Exploitability
Impact
Vector string
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H Attack Vector Network
Attack Complexity High
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High
Threat Intelligence
EPSS Exploit Probability
98.4% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available
Weaknesses 1
CWE-770
Affected Products 14
| Vendor | Product | Version | Range |
|---|---|---|---|
| openbsd | openssh | 9.5 | any |
| openbsd | openssh | 9.6 | any |
| openbsd | openssh | 9.6 | any |
| openbsd | openssh | 9.7 | any |
| openbsd | openssh | 9.7 | any |
| openbsd | openssh | 9.8 | any |
| openbsd | openssh | 9.8 | any |
| openbsd | openssh | 9.9 | any |
| openbsd | openssh | 9.9 | any |
| canonical | ubuntu_linux | 24.04 | any |
| canonical | ubuntu_linux | 24.10 | any |
| debian | debian_linux | 11.0 | any |
| debian | debian_linux | 12.0 | any |
| debian | debian_linux | 13.0 | any |
References 15
- seclists.org http://seclists.org/fulldisclosure/2025/Feb/18
- seclists.org http://seclists.org/fulldisclosure/2025/May/7
- seclists.org http://seclists.org/fulldisclosure/2025/May/8
- access.redhat.com https://access.redhat.com/security/cve/CVE-2025-26466
- bugzilla.redhat.com https://bugzilla.redhat.com/show_bug.cgi?id=2345043
- bugzilla.suse.com https://bugzilla.suse.com/show_bug.cgi?id=1237041
- seclists.org https://seclists.org/oss-sec/2025/q1/144
- security-tracker.debian.org https://security-tracker.debian.org/tracker/CVE-2025-26466
- security.netapp.com https://security.netapp.com/advisory/ntap-20250228-0002/
- ubuntu.com https://ubuntu.com/security/CVE-2025-26466
- openwall.com https://www.openwall.com/lists/oss-security/2025/02/18/1
- openwall.com https://www.openwall.com/lists/oss-security/2025/02/18/4
- qualys.com https://www.qualys.com/2025/02/18/openssh-mitm-dos.txt
- vicarius.io https://www.vicarius.io/vsociety/posts/cve-2025-26466-detection-script-memory-consumption-vulnerability-in-openssh
- vicarius.io https://www.vicarius.io/vsociety/posts/cve-2025-26466-mitigation-script-memory-consumption-vulnerability-in-openssh
Remediation
No remediation data recorded yet
Check vendor advisories and the NVD entry for patch availability.