CVE-2026-89818: Linux

High severity, CVSS 7.1. EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu/vcn: fix integer overflow in dec_msg buffer count check If the supplied msg[2] (num_buffers) is 0x3FFFFFFF, the expression 6 + num_buffers * 4 wraps to 2 and the bounds check passes, letting the parser loop far past the end of the message BO. Triggering it additionally requires a ~4GiB mapping so that msg[1] survives the earlier "header does not fit in BO" check. Rewrite the test in division form, which is overflow-free by construction. Also update the message to reflect that msg is invalid.

Affected products

• Linux Linux: from 6.1.175, before 6.1.188 (fixed in 6.1.188); from 6.6.140, before 6.6.157 (fixed in 6.6.157); from 6.12.90, before 6.12.110 (fixed in 6.12.110); from 6.18.32, before 6.18.51 (fixed in 6.18.51); from 5.15.209, before 5.16 (fixed in 5.16); from 7.0.9, before 7.1 (fixed in 7.1); …

Published 2026-09-16. Last modified 2026-09-16.