SB2026082792 - Integer overflow in Linux kernel s390 crypto driver

Description

This security bulletin contains information about 1 vulnerability.

1) Integer overflow (CVE-ID: CVE-2026-80546)

CWE-ID: CWE-190 - Integer overflow

CVSSv4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a local user to execute arbitrary code or cause a denial of service.

The vulnerability exists due to integer overflow and missing minimum size validation in the xcrb_msg_to_type6cprb_msgx() function when copying and processing user-supplied CPRB data from userspace. A local user can provide a crafted control block and length values to execute arbitrary code or cause a denial of service.

The issue involves overflow conditions in aligned length and sum calculations, as well as insufficient validation before reading CPRBX structure fields from a userspace buffer.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/35ac6754ba6da45fd193f5ce3f665f7490b830d5
• https://git.kernel.org/stable/c/50fe5133dcb46449daf2435fa705264364411129