CVE-2026-80554
CriticalCVSS 9.3Summary
In the Linux kernel, in the s390/vfio_ccw subsystem, there is no limit on the number of channel program segments. Processing is recursive, which can lead to exceeding the global limit and potential issues.
Risk Assessment
Lack of limit could allow an attacker to exhaust resources or cause system malfunction.
Recommendation
Apply the kernel patch that imposes a limit on the number of segments until the logic is rewritten to be non-recursive.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: s390/vfio_ccw: Limit the number of channel program segments The processing of channel programs, and the CCWs within them, is done recursively. As such, there is an arbitrary (but not architectural) limit to the number of CCWs that can exist in a single channel program. The vfio-ccw logic breaks these channel programs into segments whenever it encounters a Transfer-In-Channel (TIC) CCW, and the combined number of segments count towards the global limit. Impose an equivalent limit to the number of segments until such logic can be made non-recursive.