CVE-2026-12343
MediumCVSS 6.5Exploitation Probability (EPSS)
Low risk14th percentile - higher than 14% of all known CVEs
Summary
IBM MQ allows an authenticated attacker to cause a denial of service due to improper validation of RFH2 message header fields in queued publish/subscribe operations.
Risk Assessment
Improperly validated RFH2 headers can make the publish/subscribe service unavailable and disrupt message distribution.
Recommendation
Update IBM MQ to a patched version and consider limiting trust in RFH2 headers received from clients.
Other vulnerabilities in IBM MQ
See all- CVE-2026-12351Critical
IBM MQ versions 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 LTS, and 10.0.0.0 could allow a remote attacker to execute arbitrary code due to unsafe JNDI lookup processing when the IVT application is deployed.
- CVE-2026-14511Medium
IBM MQ 9.4.5.0 through 9.4.5.1 could allow an authenticated user to cause a denial of service by sending a specially crafted message that crashes consuming applications. The impact is on availability.
- CVE-2026-12727Medium
IBM MQ could allow an authenticated attacker to cause process instability due to an off-by-one buffer overflow when processing specially crafted object names. This may lead to service disruption.
- CVE-2026-12670Medium
IBM MQ contains a vulnerability that allows an authenticated attacker to cause a denial of service through a specially crafted message that triggers excessive memory operations during character set conversion.
- CVE-2026-12669Low
IBM MQ could allow an authenticated attacker to trigger a minor out-of-bounds read when sending malformed compressed data, though the data is not disclosed and the request is rejected.
- CVE-2026-12665High
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. The vulnerability occurs in the TLS certificate processing.
- CVE-2026-12350Medium
IBM MQ allows an authenticated attacker to cause a denial of service by sending a specially crafted asynchronous consume request that crashes the queue manager agent process.
- CVE-2026-12155Medium
IBM MQ allows an authenticated attacker to cause a denial of service by sending specially crafted multicast status messages that trigger a NULL pointer dereference.
- CVE-2026-11831Medium
IBM MQ allows an authenticated attacker to cause a limited denial of service and obtain very limited information about process memory layout due to an out-of-bounds read when processing a specially crafted client request.
- CVE-2026-11829Medium
IBM MQ allows an authenticated attacker to cause a denial of service due to improper validation of offset values in MQOPEN requests.
Original NVD description (English source)
IBM MQ could allow an authenticated attacker to cause a denial of service due to improper validation of RFH2 message header fields in queued publish/subscribe operations.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS