SB20260824254 - Improper access control in Linux kernel vhost driver
Published: August 24, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Improper access control (CVE-ID: CVE-2026-74580)
CWE-ID: CWE-284 - Improper Access Control
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 access memory outside the intended IOTLB-mapped region.
The vulnerability exists due to improper access control in the vhost vring metadata cache in drivers/vhost/vhost.c when reconfiguring vring addresses or vring size through vhost ioctls while a device IOTLB is attached. A local user can issue crafted vring reconfiguration ioctls after populating the metadata cache to access memory outside the intended IOTLB-mapped region.
The issue occurs because stale cached metadata mappings may continue to be used after live vring reconfiguration, causing subsequent used ring updates or descriptor fetches to use translations based on the old mapping.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/13fa6f32a56a386a82bd7451644c494beed034af
- https://git.kernel.org/stable/c/5224bd37e37d36076a550d99b2aebba33939fd95
- https://git.kernel.org/stable/c/54617e9119be2eb728ecdd8d977b99c99d4c498a
- https://git.kernel.org/stable/c/6fa3e9b1fe856259555a7e22f3f3082e7827fd9b
- https://git.kernel.org/stable/c/b70ebe0bba254e093dd5fd4c0c170941ce83eb85
- https://git.kernel.org/stable/c/cf363a7a02ce132ef1f58084fdb13e1a3b7da7e7
- https://git.kernel.org/stable/c/de845981da67a6b049080c87e605130b0c30adc5
- https://git.kernel.org/stable/c/f1e21108e3ddfcce62f6cad4ebd7b5674543c9e6