CVE-2026-123158: OpenBSD OpenSSH exploited

Advisory generated from the CVE record, CISA, Exploit Observer and VEDAS: what it is, whether it is exploited, who is affected, and how to fix and detect it.

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.

Description quoted from the CVE record (assigned by mitre, published 2026-11-05).

Weakness: CWE-394 Unexpected Status Code or Return Value

How it can be exploited

Exploitable over the network with high attack complexity needing no privileges and no user interaction. Impact: confidentiality high, integrity high, availability high. CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

CISA assessment (SSVC): CISA assesses that a public proof of concept exists. Automatable: no. Technical impact: total.

On CISA KEV since: 2026-11-09
US federal deadline: 2026-11-12
Ransomware use: Not known

Public exploit evidence (Exploit Observer)

Exploit Observer found 12 code repositories and 2 research write-ups naming this CVE.

Code repositories that name a CVE are often scanners, copies or fakes, and some are malware. Read the code before running anything.

See all 17 references on Exploit Observer

Live scores

EPSS: 0.010
low predicted chance of attack
VEDAS: 0.974
strong exploit evidence
On CISA KEV: Yes, since 2026-11-09
Detection rule: No public rule yet

Who is affected

Product	Affected	Not affected
OpenBSD OpenSSH	before 10.6p2	Not stated

Version ranges exactly as the CVE record states them. “Before X” means X is the first fixed version.

How to fix it

Fixed versions stated in the CVE record: 10.6p2.

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.

Vendor guidance:

How to detect it

There is no open VEDAS detection rule for this bug yet. It is listed on the detection gaps page if CISA has confirmed attacks.

Advisories on this CVE

OpenSSH password bypass on Alpine and musl without PAM: locked accounts accept long passwords (full advisory)

References

Exploit code

https://sshhole.com (exploit)

Other references

Other databases

Where this comes from

This advisory is generated automatically by VEDAS from: CVE.org record, CISA KEV, cve-scores (EPSS and VEDAS), Exploit Observer. Text in quotes is reproduced from the source; everything else is a fixed template filled with source fields. Nothing here is written by a language model. Check the vendor advisory before acting, and read how VEDAS and Exploit Observer work, and their limits.

CVE-2026-123158: OpenBSD OpenSSH Unexpected Status Code or Return Value Vulnerability