Skip to main content
VulnerabilityPublished Updated

CVE-2026-80551: Linux kernel · s390/vfio_ccw: Ensure first IDAW remains constant

Affects Linux kernelSource CVE Database V5

0
Compare

Not known to be exploited · CVSS 9.3 Critical · fixed in fc59e9482117ebdccd6dc7fa8082f8b980fd021e : patch Linux kernel as a priority.

Data as of 30 Oct 2026, 13:17 UTC

CVSS 3.1 base score
9.3Critical
How severe the flaw is on the 0–10 CVSS scale.

Thin evidence

One scorer or none
CVSS scores by source
CNA (Linux)CVSS 3.19.3
CISA SSVC
Exploitation
No evidence of active exploitation and no public proof of concept
Automatable
Attackers cannot reliably automate steps 1–4 of the kill chain
Technical impact
Total control over the software or total information disclosure

CISA SSVC assessment, 2026-10-16.

Patch
Available – fixed in fc59e9482117ebdccd6dc7fa8082f8b980fd021e, 565bef268d75bf7df665bce6923a88cd0eb74592, 460b977a4e71cc319fdadf91c193ec3beaa57263 +3
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 26 Aug 2026

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponized: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq 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 30 Oct 2026.

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

ProductAffectedFixed in
LinuxLinuxAffected
  • ≥ 01aa26c672c0eb771de4aaa2a8ccf6055778887b, < fc59e9482117ebdccd6dc7fa8082f8b980fd021e
Fixed in
  • fc59e9482117ebdccd6dc7fa8082f8b980fd021e
LinuxLinuxAffected
  • ≥ 01aa26c672c0eb771de4aaa2a8ccf6055778887b, < 565bef268d75bf7df665bce6923a88cd0eb74592
Fixed in
  • 565bef268d75bf7df665bce6923a88cd0eb74592
LinuxLinuxAffected
  • ≥ 01aa26c672c0eb771de4aaa2a8ccf6055778887b, < 460b977a4e71cc319fdadf91c193ec3beaa57263
Fixed in
  • 460b977a4e71cc319fdadf91c193ec3beaa57263
LinuxLinuxAffected
  • ≥ 01aa26c672c0eb771de4aaa2a8ccf6055778887b, < 08ef2a82115690d6e229615872ac1731af732497
Fixed in
  • 08ef2a82115690d6e229615872ac1731af732497
LinuxLinuxAffected
  • ≥ 01aa26c672c0eb771de4aaa2a8ccf6055778887b, < 5b7c23440343e336259cd45017cc901a744c41b0
Fixed in
  • 5b7c23440343e336259cd45017cc901a744c41b0
LinuxLinuxAffected
  • ≥ 01aa26c672c0eb771de4aaa2a8ccf6055778887b, < 0d46c2565f173bcddcdcaf44a4f69789a20535e2
Fixed in
  • 0d46c2565f173bcddcdcaf44a4f69789a20535e2

AI-suggested

A patch is available and has been applied in the Linux kernel versions identified by the fixed commit hashes. Users should update to a fixed Linux kernel version to remediate this vulnerability. Since this is a kernel-level issue, applying the official kernel update is the recommended mitigation.

Description

CVE-2026-80551 is a critical vulnerability in the Linux kernel's s390/vfio_ccw subsystem. It involves improper handling of the first IDAW (I/O Descriptor Address Word) in a list, which does not need to be aligned on a 2K/4K boundary like subsequent IDAWs. The vulnerability was addressed by ensuring the first IDAW remains constant between reads to maintain a consistent set of IDAWs.

References

Community reviews

Loading reviews…