November 13, 2026 Follow Egret
CVE-2026-123158 · CVE record: PUBLISHED

OpenBSD OpenSSH Unexpected Status Code or Return Value Vulnerability

OpenBSD OpenSSH

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.

Exploitation evidence

Known exploited · CISA KEV listed

Added 2026-11-09. Ransomware campaign use: Unknown.

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.

CISA due date: 2026-11-12. This is the catalog’s deadline, not an assessment of your organization’s exposure.

KEV checked 13 Nov 2026, 00:20 Jerusalem · Original catalog ↗

Reported products and versions

OpenBSD / OpenSSH

Default status: unaffected

  • affected: 0 to < 10.6p2 (custom)

Fixes and workarounds

No explicit solution text in the downloaded CVE record. Consult the vendor advisory; unaffected version ranges are shown above as reported, not inferred as a patch recommendation.

Sources and related reporting

CVE Program record ↗ · Download tracked evidence as JSON

Monitored source mentions

Shared CVE identifiers link source mentions; they do not establish that the reports describe the same incident.

Reviewed Egret reports

Observed change timeline

History begins when Egret first downloads each source. It is not the complete upstream CVE history.

12 Nov 2026, 18:20 Jerusalem · EPSS observation updated

Stored EPSS snapshot at this observation.

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11 Nov 2026, 00:20 Jerusalem · CVE Program record changed

Stored CNA snapshot at this observation.

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10 Nov 2026, 18:20 Jerusalem · EPSS observation updated

Stored EPSS snapshot at this observation.

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10 Nov 2026, 00:20 Jerusalem · EPSS observation updated

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10 Nov 2026, 00:20 Jerusalem · CVE Program record changed

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10 Nov 2026, 00:20 Jerusalem · CISA KEV status changed

Stored KEV snapshot at this observation.

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  "knownRansomwareCampaignUse": "Unknown",
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