The Arm Mali GPU kernel driver allows privilege escalation or information disclosure because GPU memory operations are mishandled, leading to a use-after-free. This affects Bifrost r0p0 through r28p0 before r29p0, Valhall r19p0 through r28p0 before r29p0, and Midgard r4p0 through r30p0.
Weakness
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory “belongs” to the code that operates on the new pointer.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Bifrost_gpu_kernel_driver | Arm | r0p0 (including) | r29p0 (excluding) |
| Midgard_gpu_kernel_driver | Arm | r4p0 (including) | r31p0 (excluding) |
| Valhall_gpu_kernel_driver | Arm | r19p0 (including) | r29p0 (excluding) |
Potential Mitigations
References
- https://developer.arm.com/support/arm-security-updates
- https://developer.arm.com/support/arm-security-updates/mali-gpu-kernel-driver
- https://github.com/lntrx/CVE-2021-28663
- https://developer.arm.com/support/arm-security-updates
- https://developer.arm.com/support/arm-security-updates/mali-gpu-kernel-driver
- https://github.com/lntrx/CVE-2021-28663
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-28663