Vulnerability · Published Nov 5, 2026 · Assigned by mitre
CVE-2026-123158
High 8.1
In plain English
A high-severity security flaw in OpenSSH from OpenBSD. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 1.0% (higher than 62% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code. Fixed versions are available - upgrade the affected package.
Official description
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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.20 | openssh | 9.7_p1-r6 | ALPINE-CVE-2026-123158 |
| Alpine:v3.21 | openssh | 9.9_p2-r1 | ALPINE-CVE-2026-123158 |
| Alpine:v3.22 | openssh | 10.0_p1-r11 | ALPINE-CVE-2026-123158 |
| Alpine:v3.23 | openssh | 10.2_p1-r1 | ALPINE-CVE-2026-123158 |
| Alpine:v3.24 | openssh | 10.3_p1-r2 | ALPINE-CVE-2026-123158 |
| Debian:12 | openssh | no fix listed | DEBIAN-CVE-2026-123158 |
| Debian:13 | openssh | no fix listed | DEBIAN-CVE-2026-123158 |
| Debian:14 | openssh | no fix listed | DEBIAN-CVE-2026-123158 |
| Debian:14 | openssh-gssapi | no fix listed | DEBIAN-CVE-2026-123158 |
| Ubuntu:22.04:LTS | openssh | no fix listed | UBUNTU-CVE-2026-123158 |
| Ubuntu:24.04:LTS | openssh | no fix listed | UBUNTU-CVE-2026-123158 |
| Ubuntu:26.04:LTS | openssh | no fix listed | UBUNTU-CVE-2026-123158 |
| Ubuntu:26.10 | openssh | no fix listed | UBUNTU-CVE-2026-123158 |
| Ubuntu:26.10 | openssh-gssapi | no fix listed | UBUNTU-CVE-2026-123158 |
| Ubuntu:22.04:LTS | openssh-ssh1 | no fix listed | UBUNTU-CVE-2026-123158 |
| Ubuntu:24.04:LTS | openssh-ssh1 | no fix listed | UBUNTU-CVE-2026-123158 |
| Ubuntu:26.04:LTS | openssh-ssh1 | no fix listed | UBUNTU-CVE-2026-123158 |
| Ubuntu:26.10 | openssh-ssh1 | no fix listed | UBUNTU-CVE-2026-123158 |
Affected products (as reported)
Weakness: CWE-394 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
References
- https://www.openssh.org/releasenotes.html#10.6p2
- https://github.com/openssh/openssh-portable/commit/4353fdc43ef646c43a8dda7025cc1a898caf1482
- https://news.ycombinator.com/item?id=50377976
- https://news.ycombinator.com/item?id=50378228
- https://marc.info/?l=openssh-unix-dev&m=179388064263131&w=2
- https://hachyderm.io/@damienmiller/117563026759098135
- https://github.com/predkambrij/sshhole-repro
- https://github.com/leonjza/sshhole-lab
- https://alpinelinux.org/posts/2026-11-05-openssh-password-authentication-bypass/
- https://news.ycombinator.com/item?id=50379704
- https://github.com/google/goonami-scanner/pull/277
- https://sshhole.com exploit