CVE-2026-89818
Published: September 18, 2026Last modified: September 18, 2026
Description
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.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 7.1 |
| Attack Vector | LOCAL |
| Attack complexity | LOW |
| Privileges required | LOW |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | HIGH |
| Integrity impact | NONE |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | linux-lts | Vulnerable (6.1.182-r0) |
| 25 LTS | linux-lts | Vulnerable (6.12.103-r0) | |
| Stream | linux-lts | Vulnerable (6.18.46-r0) |
References
- https://git.kernel.org/stable/c/47799e1f893d47d8af231710a61065e3ec8a13e8
- https://git.kernel.org/stable/c/4d7390530853eb7befda9cc786e4c86e8ad7ac9e
- https://git.kernel.org/stable/c/6dceaeceaa7c8396339f3ea34b0110cb912ca61b
- https://git.kernel.org/stable/c/7e28853c78c20bb8ba4c1dba702430cd05e09f76
- https://git.kernel.org/stable/c/9ae19bd60891bea0a7b7504cc8dbfe74570ac3b3
- https://git.kernel.org/stable/c/c2340281be4ddacb8c203e2bce59b126d1d6c4c8