SB2026102247 - Type conversion in Linux kernel s390 cio driver

Description

This security bulletin contains information about 1 vulnerability.

1) Type conversion (CVE-ID: CVE-2026-98475)

CWE-ID: CWE-704 - Type conversion

CVSSv4: 6.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a local user to potentially corrupt memory or cause a denial of service through firmware writes to an incorrect memory address.

The vulnerability exists due to missing virtual-to-physical address translation in the s390 channel measurement facility when configuring the measurement block address for extended format channel measurement data. A local user can potentially trigger affected channel measurement processing to cause firmware to store measurement data at an incorrect absolute address, which may corrupt memory or cause a denial of service.

The incorrect addressing occurs on kernels built with CONFIG_RANDOMIZE_IDENTITY_BASE=y.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/748ec2f7f5df9b4fc742546a8bfc8aa5d847353e
• https://git.kernel.org/stable/c/7f78226eb743b362f52b212d7763801642539d1c
• https://git.kernel.org/stable/c/b11f369be31ea11c746833e4d3ad51dcd6b5fa2b
• https://git.kernel.org/stable/c/f4d04425e66af2ecee9d1a49ae0484436f3c2fd1