CVE-2026-99126
kernel: kernel: Denial of service via null pointer dereference in s390/ctcm
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · October 28, 2026
Updated · October 29, 2026
Description
A flaw was found in the Linux kernel's s390 CTCM (Channel-to-Channel) driver. A denial of service (DoS) can occur when the driver processes invalid Exchange Station Identification (XID) data during channel negotiation. If a peer XID is missing or a channel pairing mismatch occurs, the driver attempts to record a validation error on an uninitialized data structure, triggering a null pointer dereference. This flaw allows a peer or attacker to cause a kernel crash.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.1 · 6.5CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE-476 · NULL Pointer Dereference