CVE-2026-123158OpenSSH Vulnerability
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).
Published Nov 5, 2026 · Updated Nov 6, 2026 · Also known as EUVD-2026-117552, GHSA-4fcc-vm97-gx3x
Key Facts
Patch immediately- CVE-2026-123158 is a high-severity vulnerability (CVSS 8.1 v3.1) affecting OpenSSH (Openbsd).
- It is exploited in the wild, listed in Industry KEV feed since Nov 6, 2026. A public exploit is reported by tracking sources, but no code link is listed yet.
- EPSS estimates a 1.0% probability of exploitation in the next 30 days.
- Fixed versions are available, including OpenSSH 10.6p2.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
Scores
CVSS v3.1
8.1
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
1.0%
Higher than 62.2% of all scored CVEs
Exploit maturity
Exploited (KEV)
ATLAS score
70/100
Publication score, see How it works
Exploitation Verdict
KEV listed
Nov 6, 2026
1 days after publication
Federal due date
None
No federal due date
Ransomware use
Not reported
Attributed actors
None named
Exploit & Defence Guidance
Exploit maturity
Exploited (KEV)
Public exploit code
10
Proof-of-concept links
In-the-wild evidence
2
Reports of active use
Advisories And Exploit References
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.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| Industry KEV feed | Nov 6, 2026 | n/a | Not reported |
Affected Products
3 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| OpenSSHOpenbsd | See advisory | 10.6p2 |
Patched Releases
OpenSSH
10.6p2
Timeline
Publicly disclosed
Nov 5, 2026
Added to Industry KEV feed
Nov 6, 2026
Last updated
Nov 6, 2026
Weakness Type
- CWE-303 Incorrect Implementation of Authentication Algorithm
- CWE-394 Unexpected Status Code or Return Value
References
- advisorycve.org · CVERecord
- advisorynvd.nist.gov · CVE-2026-123158
- exploitsshhole.com
- exploitVulnCheck exploitation report
- otheralpinelinux.org · 2026-11-05-openssh-password-authentication-bypa…
FAQ
Common Questions.
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).
Affected: OpenSSH (Openbsd). The full list is in the CVE brief.
It is exploited in the wild, listed in Industry KEV feed since Nov 6, 2026.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
A public exploit is reported by tracking sources, but no code link is listed yet.
Fixed versions are available, including OpenSSH 10.6p2.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
Is CVE-2026-123158 On Your Attack Surface?
Brandefense matches it against the products discovered on your perimeter and opens a finding the day a CVE like this is listed.
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