Skip to content
Fencer Intel
high 8.1

CVE-2026-123158 kev in the critical feed json

sshd in OpenSSH before 10.6p2 on Linux, when musl libc is used without PAM, lacks a workaround for a password authentication bypass (relate…

published 4d ago modified 3h ago also EUVD-2026-117552

cvss
8.1
version 3.1, CNA
cisa kev
Exploited
added 2026-11-09
epss
1.0%
EPSS 1.0% chance of exploitation in 30 days, percentile 63%
public exploits
0
none known

Summary

sshd in OpenSSH before 10.6p2 on Linux, when musl libc is used without PAM, lacks a workaround for a password authentication bypass (related to misinterpretation of whether a string is intended to be a password hash). For some configurations of accounts, any password between 256 and 1024 characters succeeds. An example of a platform using musl libc without PAM is Alpine Linux.

Patch / fix

cisa required action Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

  • OpenBSD OpenSSH 10.6p2
  • openssh Debian 14 1:10.6p2-1
  • openssh-gssapi Debian 14 1:10.6p2-1

debian advisories DEBIAN-CVE-2026-123158

  • openssh Alpine 3.16 9.0_p1-r6
  • openssh Alpine 3.17 9.1_p1-r7
  • openssh Alpine 3.18 9.3_p2-r4
  • openssh Alpine 3.19 9.6_p1-r3
  • openssh Alpine 3.20 9.7_p1-r6
  • openssh Alpine 3.21 9.9_p2-r1
  • openssh Alpine 3.22 10.0_p1-r11
  • openssh Alpine 3.23 10.2_p1-r1

alpine advisories ALPINE-CVE-2026-123158

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

Is CVE-2026-123158 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

Check with Fencer

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-123158 updated cvss 9.8

openssh: OpenSSH: Password authentication bypass via password hash misinterpretation

  • Red Hat Enterprise Linux 6 openssh, openssh-ldap, openssh-server, openssh-askpass, openssh-clients, pam_ssh_agent_auth Red Hat Enterprise Linux 7 openssh, openssh-cavs, openssh-ldap, openssh-keycat, openssh-server, openssh-askpass, +3 more Red Hat Enterprise Linux 8 openssh, openssh-cavs, openssh-ldap, openssh-keycat, openssh-server, openssh-askpass, +2 more Red Hat Enterprise Linux 9 openssh, openssh-keycat, openssh-server, openssh-askpass, openssh-clients, pam_ssh_agent_auth Red Hat Enterprise Linux 10 openssh Red Hat Hardened Images openssh, openshell
    +2 more products
    Red Hat OpenShift Container Platform 4 openshift/ose-rhel-coreos-8, openshift/ose-rhel-coreos-9 Red Hat OpenShift Container Platform 5 openshift/ose-rhel-coreos-9
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Timeline

  1. Published
  2. Added to CISA KEV
  3. CISA SSVC: exploitation active
  4. CISA patch deadline

Known exploited

Added
yesterday
Patch by
2026-11-12 (tomorrow)
Ransomware
Not known
Required action
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
Vendor, product
OpenBSD, OpenSSH
CISA name
OpenBSD OpenSSH Unexpected Status Code or Return Value Vulnerability

CISA SSVC

Exploitation
Active, exploited in the wild
Automatable
no
Technical impact
total
Assessed
7h ago

Exploit prediction

1.01% chance of exploitation in the next 30 days, higher than 63% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • sshhole.com https://sshhole.com referenced PoC, tagged "exploit" by a source, unverified
  • github.com https://github.com/predkambrij/sshhole-repro referenced PoC, tagged "exploit" by a source, unverified
  • github.com https://github.com/leonjza/sshhole-lab referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 8.1 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

  • OpenBSD OpenSSH

Classification

Weakness
  • CWE-394 Unexpected Status Code or Return Value

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.