CVE-2026-123158
What it is
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.
At a glance
- Exploitability
- Can be exploited over the network without logging in. High risk of data exposure, data tampering, service disruption.
- In the wild
- CISA lists this as exploited in real attacks. Treat as urgent.
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- ReservedThe CVE id was reserved by its CNA
- PublishedDisclosed publicly on CVE.org and NVD
- 2026-11-09 Exploited in the wildAdded to CISA's Known Exploited Vulnerabilities list
- Last updatedMost recent change to the record
- 2026-11-12 Remediation deadlineCISA's due date for federal agencies to fix it
Why it ranks here
- Exploited in the wild: yes, CISA lists it. This puts it above everything that is not.
- Exploit odds: 1.0% in the next 30 days (EPSS).
- Severity: 8.1 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Added to CISA KEV
- 2026-11-09
- Exploit probability
- 1.0% · EPSS, next 30 days
- Weakness
- CWE-394
- Record status
- Analyzed
Affected
- Openbsd OpenSSH < 10.6
- Openbsd OpenSSH 10.6
Attack profile CVSS 3.1 · 8.1
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-123158.md and follow it. Check whether this project is affected by CVE-2026-123158. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://github.com/openssh/openssh-portable/commit/4353fdc43ef646c43a8dda7025cc1a898caf1482
- https://marc.info/?l=openssh-unix-dev&m=179388064263131&w=2
- https://github.com/google/goonami-scanner/pull/277
References
- https://github.com/leonjza/sshhole-lab
- https://github.com/openssh/openssh-portable/commit/4353fdc43ef646c43a8dda7025cc1a898caf1482
- https://github.com/predkambrij/sshhole-repro
- https://hachyderm.io/@damienmiller/117563026759098135
- https://marc.info/?l=openssh-unix-dev&m=179388064263131&w=2
- https://news.ycombinator.com/item?id=50377976
- https://news.ycombinator.com/item?id=50378228
- https://www.openssh.org/releasenotes.html#10.6p2
- http://www.openwall.com/lists/oss-security/2026/11/09/27
- https://alpinelinux.org/posts/2026-11-05-openssh-password-authentication-bypass/
- https://github.com/coollabsio/coolify/discussions/12484
- https://github.com/google/goonami-scanner/pull/277
- https://github.com/panubo/docker-sshd/issues/93
- https://news.ycombinator.com/item?id=50379704
- https://isc.sans.edu/diary.html?storyid=33498
- https://sshhole.com
- https://sshole.events.greynoise.io/
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-123158