CVE-2026-12665 Critical · 9.8 EPSS 0.3%
IBM MQ could allow a remote attacker to execute arbitrary code due to a stack buffer overflow when processing TLS certificates with malformed distinguished names during channel connection establishment.
IBM · MQ Operator
Summary
The flaw is a stack-based buffer overflow in the IBM MQ Operator product, triggered when it processes TLS certificates containing malformed distinguished names during channel connection establishment. An attacker can exploit it over the network to execute arbitrary code, with no privileges or user interaction required, by presenting such a certificate during channel setup.
Heading is the official description · NVD
Priority scorePatchfirst’s 0 to 100 ranking. It adds points for CISA KEV listing, ransomware use, EPSS, threat reports, public exploit code and CVSS. Every CVE page shows the breakdown. Breakdown
13.5 / 100
- Exploited
- Not confirmed
- Reports
- 0
- Tactics
- 0/15
Exploitation timelineDated milestones for a CVE: when it was disclosed, when exploit code became public, when exploitation was confirmed, and when threat reports named it.
Disclosed on 19 Oct 2026. No public exploit code or confirmed exploitation is recorded.
MITRE ATT&CKA public catalogue of the techniques attackers use, maintained by MITRE. Patchfirst uses it to describe what attackers do with a vulnerability. techniques
No techniques linkedNo ATT&CK techniques are linked to this CVE yet. MITRE CTID has not mapped it, and no report passage in the corpus ties it to a technique.
What security researchers reported
Not named in any threat report yetAlso mentioned in 5 community threat pulses (AlienVault OTX)
Weaker evidencePulses are indicator collections that anyone can publish. A mention is not confirmation of exploitation.
- Known_Cve | Oct 28, 2026 | Part 1/327 Oct 2026
- Known_Cve | Oct 27, 2026 | Part 1/326 Oct 2026
- Known_Cve | Oct 24, 2026 | Part 1/323 Oct 2026
- Known_Cve | Oct 23, 2026 | Part 2/322 Oct 2026
- Known_Cve | Oct 22, 2026 | Part 3/421 Oct 2026