CVE-2026-12538: IBM MQ Appliance · Buffer Underrun
Affects IBM MQ ApplianceSource CVE Database V5
Not known to be exploited · CVSS 5.4 Medium.
Data as of 4 Nov 2026, 21:42 UTC
Thin evidence
One scorer or none| CNA (ibm) | CVSS 3.1 | 5.4 |
|---|
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:LExploitation evidence
Disclosed: evidence found.
CVE published 4 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 4 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| IBMMQ Appliance | Affected
| Fixed in– |
CPE configurations (4)
cpe:2.3:a:ibm:mq_appliance:9.4:*:*:*:*:*:*:*cpe:2.3:a:ibm:mq_appliance:9.4.0:*:*:*:*:*:*:*cpe:2.3:a:ibm:mq_appliance:9.4.0.0:*:*:*:*:*:*:*cpe:2.3:a:ibm:mq_appliance:9.4.1.0:*:*:*:*:*:*:*
AI-suggested
Until a fix is available, restrict access to trusted authenticated users and monitor for unusual activity related to message header processing.
Description
CVE-2026-12538 is a buffer underrun vulnerability in IBM MQ Appliance versions 9.4.0.0 through 9.4.0.26, 9.4.1.0 through 9.4.5.3, and 10.0.0.1 through 10.0.0.5. It allows an authenticated attacker to obtain sensitive information or cause a denial of service by exploiting improper validation of message header structure length fields.