SB20260925129 - Resource exhaustion in Linux kernel selftests mm

Description

This security bulletin contains information about 1 vulnerability.

1) Resource exhaustion (CVE-ID: CVE-2026-93243)

CWE-ID: CWE-400 - Resource exhaustion

CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to improper locked-page resource accounting in the Linux kernel secretmem feature when mapping and unmapping secret memory ranges. A local user can repeatedly map and unmap secret memory ranges to consume all available system memory with unevictable folios and cause a denial of service.

A secretmem file descriptor can be passed between processes and inherited across fork.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/3b4f72bdddff69819d665395376329ef21f37a06
• https://git.kernel.org/stable/c/853043cb129473ff2fa0090602be944d96b9d5c9
• https://git.kernel.org/stable/c/97d34aa65c29cca85e3e9050f4c936389b38a054