SB2026072778 - Out-of-bounds read in Linux kernel resctrl

Description

This security bulletin contains information about 1 vulnerability.

1) Out-of-bounds read (CVE-ID: CVE-2026-64477)

CWE-ID: CWE-125 - Out-of-bounds read

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 an out-of-bounds access in the resctrl RMID reader and limbo handler when offlining a monitoring domain with SNC enabled. A local user can trigger CPU offlining for a monitoring domain with an empty cpu_mask to cause a denial of service.

The issue occurs when LLC occupancy is tracked and the monitoring domain is going offline, causing a NUMA node lookup to be performed with nr_cpu_ids.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/58c5ec23b1a238eb75cb0aba6f69d8f9e68ef0b2
• https://git.kernel.org/stable/c/be1567992417dc92133e74126de7a6066c825ac9
• https://git.kernel.org/stable/c/ebc300b7ee0c669fa76a7a8858298ff32e296103
• https://git.kernel.org/stable/c/fc16126cc11d9f507130bf84ab137ee0938c900e