Strix
63.5K

CVE-2026-80550

HIGHCVSS 7.9/10

Last modified

CVE-2026-80550 is a high-severity vulnerability rated 7.9/10 on the CVSS scale. In the Linux kernel, the following vulnerability has been resolved: s390/vfio_ccw: Fix out of bounds check on CCW array The routine ccwchain_calc_length() counts the number of channel command words (CCWs) that are chained together in a single channel program, and rejects anything larger than CCWCHAIN_LEN_MAX (256) CCWs. The loop itself is "do..while (count < 257)", and while the logic in is_cpa_within_range() correctly adjusts between the 0-index array of CCWs and the count of CCWs starting at 1, this means it would look at a possible 257th CCW before ending the loop and (correctly) returning an error. Fix this by restructuring the loop to break as soon as 256 CCWs (thus indexes 0-255) are examined, without looking at memory outside the range..

Description

In the Linux kernel, the following vulnerability has been resolved: s390/vfio_ccw: Fix out of bounds check on CCW array The routine ccwchain_calc_length() counts the number of channel command words (CCWs) that are chained together in a single channel program, and rejects anything larger than CCWCHAIN_LEN_MAX (256) CCWs. The loop itself is "do..while (count < 257)", and while the logic in is_cpa_within_range() correctly adjusts between the 0-index array of CCWs and the count of CCWs starting at 1, this means it would look at a possible 257th CCW before ending the loop and (correctly) returning an error. Fix this by restructuring the loop to break as soon as 256 CCWs (thus indexes 0-255) are examined, without looking at memory outside the range.

Metrics

CVSS 3.1
7.9/10

CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:L

Affected Software

Source: CNA advisory (CVE.org). NVD analysis pending.

VendorProductVersions
LinuxLinux>= 0a19e61e6d4c6192077ead760ba0a2d350987d4c, < 0282fb1c4b638eecfe2cc558092c460911d8f7e2; >= 0a19e61e6d4c6192077ead760ba0a2d350987d4c, < 907adc667d902fafbdb2d740d57b55bd025dc4cd; >= 0a19e61e6d4c6192077ead760ba0a2d350987d4c, < f20be33d093ce7630c17ff7ed93caf7eaf8ac1a3; >= 0a19e61e6d4c6192077ead760ba0a2d350987d4c, < af3f80ca4c8b17f20f9e588def076288fdb49e65; >= 0a19e61e6d4c6192077ead760ba0a2d350987d4c, < 499a8a66b1598bfab97182aed15e0f1646074a3d; >= 0a19e61e6d4c6192077ead760ba0a2d350987d4c, < 4c2e1d359d7a2b82cdf3254e4e480af9417f99fb; >= 0a19e61e6d4c6192077ead760ba0a2d350987d4c, < d5d096cd9369e986d4e5153baa86b8b35c283e09; >= 0a19e61e6d4c6192077ead760ba0a2d350987d4c, < a005b7f1a491ffda61bff0fd0f6548f8986fb977
LinuxLinux4.12

References

Timeline

Published
Last Modified
Status
Received

Frequently Asked Questions

What is CVE-2026-80550?
In the Linux kernel, the following vulnerability has been resolved: s390/vfio_ccw: Fix out of bounds check on CCW array The routine ccwchain_calc_length() counts the number of channel command words (CCWs) that are chained together in a single channel program, and rejects anything larger than CCWCHAIN_LEN_MAX (256) CCWs. The loop itself is "do..while (count < 257)", and while the logic in is_cpa_within_range() correctly adjusts between the 0-index array of CCWs and the count of CCWs starting at 1, this means it would look at a possible 257th CCW before ending the loop and (correctly) returning an error. Fix this by restructuring the loop to break as soon as 256 CCWs (thus indexes 0-255) are examined, without looking at memory outside the range.
How severe is CVE-2026-80550?
CVE-2026-80550 has a CVSS score of 7.9/10 (HIGH severity).
How do I fix CVE-2026-80550?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

How Strix Helps

Related CVEs from 2026

View all 2026CVEs →

Are you affected by CVE-2026-80550?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST