SB2026051461 - Improper Check for Unusual or Exceptional Conditions in Linux kernel arm64 mm

Description

This security bulletin contains information about 1 vulnerability.

1) Improper Check for Unusual or Exceptional Conditions (CVE-ID: CVE-2026-43486)

CWE-ID: CWE-754 - Improper Check for Unusual or Exceptional Conditions

CVSSv4: 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/E:U/U:Clear

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

The vulnerability exists due to improper access flag handling in contpte_ptep_set_access_flags() when handling SMMU or ATS faults on individual sub-PTEs within a CONT range. A local user can trigger memory access faults to cause a denial of service.

The issue can result in an infinite fault loop on systems where page-table walkers evaluate each descriptor individually.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/05d239f2c95e66e27e7fb4e99ee07eb56e3e34b0
• https://git.kernel.org/stable/c/09d620555e59768776090073a2c59d2bc8506eb3
• https://git.kernel.org/stable/c/6f92a7a8b48a523f910ef25dd83808710724f59b
• https://git.kernel.org/stable/c/97c5550b763171dbef61e6239cab372b9f9cd4a2