CVE-2026-12666

HIGHPre-NVD 8.18.1—
EchelonGraph scoreHIGH confidence

Score 8.1 from GitHub Security Advisory (severity: HIGH) published 2026-09-15. a secondary CVSS source baseline 8.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
8.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 8.1Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

IBM MQ 9.1.0.0 through 9.1.0.37 LTS, 9.2.0.0 through 9.2.0.43 LTS, 9.3.0.0 through 9.3.0.41 LTS, 9.3.0.0 through 9.3.5.1 CD, 9.4.0.0 through 9.4.0.25 LTS, 9.4.0.0 through 9.4.5.1 CD, and 10.0.0.0 Classes for Java could allow an authenticated attacker to obtain sensitive information or cause a denial of service due to XML external entity injection in MQRFH2 header processing.

CVSS v3
8.1
EG Score
8.1(high)
EG Risk
37(Track)
EG Risk 37/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity81% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
19%
KEV
Not listed

Published

September 15, 2026

Last Modified

September 17, 2026

Advisory Details (1)

Auto-updated Sep 15, 2026
No patch confirmed yet.
generic

Security Bulletin: IBM MQ Java messaging is vulnerable to XML external entity injection (CVE-2026-12666)

https://www.ibm.com/support/pages/node/7284939

Vendor Advisories for CVE-2026-12666(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 22× in last 7d / 22× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. 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. Most recent first.

  1. 2026-09-20 20:15 UTCEPSS rescore
  2. 2026-09-20 15:07 UTCGHSA enrichment
  3. 2026-09-20 03:38 UTCGHSA enrichment
  4. 2026-09-19 16:08 UTCEG score recompute
  5. 2026-09-19 16:08 UTCGHSA enrichment
  6. 2026-09-19 04:38 UTCEG score recompute
  7. 2026-09-19 04:38 UTCGHSA enrichment
  8. 2026-09-18 19:27 UTCEPSS rescore
  9. 2026-09-18 17:08 UTCGHSA enrichment
  10. 2026-09-18 05:37 UTCEG score recompute
  11. 2026-09-18 05:37 UTCGHSA enrichment
  12. 2026-09-17 18:08 UTCEG score recompute
  13. 2026-09-17 18:08 UTCGHSA enrichment
  14. 2026-09-17 07:04 UTCGHSA enrichment
  15. 2026-09-16 19:35 UTCGHSA enrichment
  16. 2026-09-16 17:55 UTCEG score recompute
  17. 2026-09-16 17:55 UTCGHSA enrichment
  18. 2026-09-16 06:02 UTCGHSA enrichment
  19. 2026-09-15 18:33 UTCEG score recompute
  20. 2026-09-15 18:33 UTCGHSA enrichment
  21. 2026-09-15 17:23 UTCEG score recompute
  22. 2026-09-15 17:22 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-12666?
CVE-2026-12666 is a high vulnerability published on September 15, 2026. IBM MQ 9.1.0.0 through 9.1.0.37 LTS, 9.2.0.0 through 9.2.0.43 LTS, 9.3.0.0 through 9.3.0.41 LTS, 9.3.0.0 through 9.3.5.1 CD, 9.4.0.0 through 9.4.0.25 LTS, 9.4.0.0 through 9.4.5.1 CD, and 10.0.0.0 Classes for Java could allow an authenticated attacker to obtain sensitive information or cause a…
When was CVE-2026-12666 disclosed?
CVE-2026-12666 was first published in the National Vulnerability Database on September 15, 2026, with the most recent update on September 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-12666 actively exploited?
CVE-2026-12666 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 81.4% of all scored CVEs.
What is the CVSS score of CVE-2026-12666?
CVE-2026-12666 has a CVSS v3 base score of 8.1 (NVD).
How do I remediate CVE-2026-12666?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-12666, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-12666

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