CVE-2026-80550

medium Red Hat
CVSS v3 Base Score
5.5
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS Score
0.1%
Exploitation probability in 30 days
Top 97% most likely to be exploited
Attack Characteristics
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Confidentiality
None
Integrity
None
Availability
High
Published: August 26, 2026 (11 days ago)
Last Modified: August 26, 2026
Vendor: Red Hat
Source: REDHAT

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.

CWE

CWE-125

Affected Products

Red Hat Enterprise Linux 10Red Hat Enterprise Linux 6Red Hat Enterprise Linux 7Red Hat Enterprise Linux 8Red Hat Enterprise Linux 9

References

🔗 bugzilla.redhat.com 🔗 www.cve.org 🔗 nvd.nist.gov 🔗 lore.kernel.org