CVE-2025-26466CWE-770denial-of-service

CVE-2025-26466

Medium · published March 1, 2025

CVSS v3.1
5.9
EPSS
41%
Percentile
98.7
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
5.9 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.40650 · 98.7th percentile
Weakness
CWE-770 · Allocation of Resources Without Limits or Throttling
Published
2025-03-01T03:15Z
Affected products (14)
ProductVersionsFixed in
openbsd/opensshall versions—
openbsd/opensshall versions—
openbsd/opensshall versions—
openbsd/opensshall versions—
openbsd/opensshall versions—
openbsd/opensshall versions—
openbsd/opensshall versions—
openbsd/opensshall versions—
openbsd/opensshall versions—
canonical/ubuntu_linuxall versions—
canonical/ubuntu_linuxall versions—
debian/debian_linuxall versions—
debian/debian_linuxall versions—
debian/debian_linuxall versions—
References (19)
https://access.redhat.com/errata/RHBA-2025:6305 · [email protected]https://access.redhat.com/errata/RHSA-2025:6993 · [email protected]https://access.redhat.com/security/cve/CVE-2025-26466 · [email protected]https://bugzilla.redhat.com/show_bug.cgi?id=2345043 · [email protected]https://seclists.org/oss-sec/2025/q1/144 · [email protected]https://www.qualys.com/2025/02/18/openssh-mitm-dos.txt · [email protected]http://seclists.org/fulldisclosure/2025/Feb/18 · af854a3a-2127-422b-91ae-364da2661108http://seclists.org/fulldisclosure/2025/May/7 · af854a3a-2127-422b-91ae-364da2661108http://seclists.org/fulldisclosure/2025/May/8 · af854a3a-2127-422b-91ae-364da2661108https://bugzilla.suse.com/show_bug.cgi?id=1237041 · af854a3a-2127-422b-91ae-364da2661108https://security-tracker.debian.org/tracker/CVE-2025-26466 · af854a3a-2127-422b-91ae-364da2661108https://security.netapp.com/advisory/ntap-20250228-0002/ · af854a3a-2127-422b-91ae-364da2661108https://ubuntu.com/security/CVE-2025-26466 · af854a3a-2127-422b-91ae-364da2661108https://www.openwall.com/lists/oss-security/2025/02/18/1 · af854a3a-2127-422b-91ae-364da2661108https://www.openwall.com/lists/oss-security/2025/02/18/4 · af854a3a-2127-422b-91ae-364da2661108https://www.vicarius.io/vsociety/posts/cve-2025-26466-detection-script-memory-consumption-vulnerability-in-openssh · af854a3a-2127-422b-91ae-364da2661108https://www.vicarius.io/vsociety/posts/cve-2025-26466-mitigation-script-memory-consumption-vulnerability-in-openssh · af854a3a-2127-422b-91ae-364da2661108https://cert-portal.siemens.com/productcert/html/ssa-398330.html · 0b142b55-0307-4c5a-b3c9-f314f3fb7c5ehttps://www.qualys.com/2025/02/18/openssh-mitm-dos.txt · 134c704f-9b21-4f2e-91b3-4a467353bcc0
EPSS history
Timeline
  • 28 FEB 21:25Z
    Openssh: denial-of-service in openssh
    cvelistv5