CVE-2026-123158

HIGHPre-NVD 8.18.1
EchelonGraph scoreHIGH confidence

“—” beside the score: it is equal to the CVSS score beside it.

Score 8.1 from GitHub Security Advisory (severity: HIGH) published 2026-11-05. A secondary CVSS source baseline 8.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, a secondary CVSS source
Trending — 5 sources updated this weekElevated

Also known asEUVD-2026-117552 (ENISA EUVD) · GHSA-4fcc-vm97-gx3x (GitHub Security Advisories)Source: ENISA EUVD

8.1EG
EchelonGraph verdictPlan mitigationThe upstream fix is not in a release yet: until the release ships, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule at low or medium mission impact and sooner than that at high, then apply it (the SSVC decision on this page).
  • Public exploit or proof-of-concept code is available
CISA-KEV: Not listedEPSS PROB: 1.0%CVSS: 8.1Exploit: Public PoCExposed services: Not assessed

An upstream fix is merged but not yet released — mitigate (WAF / firewall / segmentation) until the release ships, then apply it.

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.

CVSS v3
8.1
EG Score
8.1HIGHhigh confidence
EG Risk
52
EG Risk 52/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity81% × 45%
Impact severity (EG Severity): CVSS 8.1 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation40% × 40%
EchelonGraph's fixed weight for EG-KEV Tier 3 (Elevated): a constant, not a probability.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low, Track* at medium and Attend at high mission impact.
Exploitation public PoC (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: An upstream fix is merged but not yet in a tagged release. Until the release ships, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule at low or medium mission impact and sooner than that at high, then apply it.
EPSS PROB
1.0%
EPSS %ILE
62nd
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (8.1): severity, escalated by confirmed exploitation. This CVE's 8.1 is its impact severity (EG Severity), not escalated.

EG Severity
8.1 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
1.0% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-07). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track* at medium mission impactTrack at low, Track* at medium and Attend at high mission impact.CISA BOD 26-04: 14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: it starts when an agency identifies the flaw on an asset and updates the CDM Agency and Federal Dashboard, and the directive counts patching, decommissioning the system or another action as remediation. Until a fixed release is applied, mitigate as this page's verdict says. In the directive's words, “Fix on system upgrade” means that, “unless conditions change”, the vulnerability “should be remediated the next time the vulnerable asset receives a scheduled major upgrade or rebuild”: its timelines are “dynamic as facts change”, and a KEV listing shortens them.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at low, Track* at medium and Attend at high mission impact.

An upstream fix is merged but not yet in a tagged release. Until the release ships, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule at low or medium mission impact and sooner than that at high, then apply it.

Exploitation public PoC (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: it starts when an agency identifies the flaw on an asset and updates the CDM Agency and Federal Dashboard, and the directive counts patching, decommissioning the system or another action as remediation. Until a fixed release is applied, mitigate as this page's verdict says. In the directive's words, “Fix on system upgrade” means that, “unless conditions change”, the vulnerability “should be remediated the next time the vulnerable asset receives a scheduled major upgrade or rebuild”: its timelines are “dynamic as facts change”, and a KEV listing shortens them.

The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

November 5, 2026

Last Modified

November 8, 2026

Advisory Details (8)

Auto-updated Nov 5, 2026
Upstream fix merged — awaiting tagged release. Sources: github_commit.
Web page

GitHub - leonjza/sshhole-lab: An sshhole lab to play and learn · GitHub

https://github.com/leonjza/sshhole-lab
Web page

GitHub - predkambrij/sshhole-repro · GitHub

https://github.com/predkambrij/sshhole-repro
Web page

Damien Miller: "OpenSSH 10.6p2 has been released with a workaroun…" - Hachyderm.io

https://hachyderm.io/@damienmiller/117563026759098135
Web page

'urgent security release: 10.6p2' - MARC

https://marc.info/?l=openssh-unix-dev&m=179388064263131&w=2
Web page

OpenSSH 10.6p2 Critical workaround for alpine without PAM | Hacker News

https://news.ycombinator.com/item?id=50377976
GitHub commit

commit 4353fdc43ef6 (openssh/openssh-portable)

Fix landed in openssh/openssh-portable commit 4353fdc43ef6 — awaiting tagged release

https://github.com/openssh/openssh-portable/commit/4353fdc43ef646c43a8dda7025cc1a898caf1482

Vendor Advisories for CVE-2026-123158(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 23× in last 7d / 23× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

  1. 2026-11-08 03:27 UTCEG score recompute
  2. 2026-11-08 03:27 UTCGHSA enrichmentGHSA-4fcc-vm97-gx3x · GitHub severity HIGH · GitHub CVSS 8.1
  3. 2026-11-08 03:06 UTCEG score recompute
  4. 2026-11-08 03:06 UTCGHSA enrichmentGHSA-4fcc-vm97-gx3x · GitHub severity HIGH · GitHub CVSS 8.1
  5. 2026-11-07 16:38 UTCEPSS rescoreEPSS 1.0% · 62nd percentile
  6. 2026-11-07 16:27 UTCEG score recompute
  7. 2026-11-07 16:27 UTCGHSA enrichmentGHSA-4fcc-vm97-gx3x · GitHub severity HIGH · GitHub CVSS 8.1
  8. 2026-11-06 16:36 UTCEPSS rescoreEPSS 1.0% · 62nd percentile
  9. 2026-11-06 16:26 UTCEG score recompute
  10. 2026-11-06 16:25 UTCGHSA enrichmentGHSA-4fcc-vm97-gx3x · GitHub severity HIGH · GitHub CVSS 8.1
  11. 2026-11-06 05:27 UTCEG score recompute
  12. 2026-11-06 05:27 UTCGHSA enrichmentGHSA-4fcc-vm97-gx3x · GitHub severity HIGH · GitHub CVSS 8.1
  13. 2026-11-06 05:03 UTCGHSA enrichmentGHSA-4fcc-vm97-gx3x · GitHub severity HIGH · GitHub CVSS 8.1
  14. 2026-11-05 21:26 UTCEG score recompute
  15. 2026-11-05 21:26 UTCGHSA enrichmentGHSA-4fcc-vm97-gx3x · GitHub severity HIGH · GitHub CVSS 8.1
  16. 2026-11-05 21:13 UTCEG score recompute
  17. 2026-11-05 21:13 UTCGHSA enrichmentGHSA-4fcc-vm97-gx3x · GitHub severity HIGH · GitHub CVSS 8.1
  18. 2026-11-05 18:27 UTCEG score recompute
  19. 2026-11-05 17:24 UTCEG score recompute
  20. 2026-11-05 17:04 UTCENISA EUVD ID recordedEUVD-2026-117552 · Source: ENISA EUVD
  21. 2026-11-05 16:27 UTCEG score recompute
  22. 2026-11-05 15:54 UTCEG score recomputeFirst assessed: 8.1 HIGH
  23. 2026-11-05 15:53 UTCMITRE cvelistV5first tracked

Publicly available exploits

(2 references)

Public exploit code is referenced for this CVE (2 GitHub PoCs). The fix is not yet in a release, so defenders should restrict or isolate affected systems accordingly until it ships.

  • GitHub PoCMaalfer/CVE-2026-123158
    Published Nov 6, 2026

    Exploit para explotar la vulnerabilidad CVE-2026-123158 (conocida como sshole).

    Open source ↗
  • GitHub PoCgabrielunknown/CVE-2026-123158_SSHole
    Published Nov 5, 2026

    CVE-2026-123158 SSHole — OpenSSH authentication bypass via musl crypt() overflow on Alpine Linux (Exploit PoC)

    Open source ↗

Frequently asked(5)

What is CVE-2026-123158?
CVE-2026-123158 is a high-severity vulnerability; its CVE record was published on November 5, 2026. 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…
When was the CVE record for CVE-2026-123158 published?
The CVE record for CVE-2026-123158 was published on November 5, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of November 8, 2026; the record at its source may have been updated since.
Is CVE-2026-123158 actively exploited?
CVE-2026-123158 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1.0% probability of exploitation in the next 30 days (62nd percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-123158?
CVE-2026-123158 has a CVSS base score of 8.1 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-123158?
An upstream fix for CVE-2026-123158 has been merged but is not yet in a tagged release. Until it ships, restrict network exposure of the affected system or apply the vendor's mitigation, then update to the release that contains the fix. The vendor advisories EchelonGraph has for CVE-2026-123158 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-123158

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