CVE-2026-89882 media: rkvdec: hevc: guard INTER_REF_PIC_SET_PRED index underflow
A local attacker can trigger an integer underflow in the RKVDEC driver, causing out-of-bounds memory reads and potential system instability.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-89882?
CVE-2026-89882 is a high-severity vulnerability in Linux, published on 16 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
media: rkvdec: hevc: guard INTER_REF_PIC_SET_PRED index underflow
st_ref_pic_set_prediction() computes the reference RPS index as st_rps_idx - (delta_idx_minus1 + 1) per HEVC spec equation 7-59. Both operands are u8, so when delta_idx_minus1 + 1 exceeds the current index the subtraction wraps and the subsequent array access at calculated_rps_st_sets[ref_rps_idx] reads far out of bounds.
A userspace V4L2 client that can open the RKVDEC m2m decoder can submit an EXT_SPS_ST_RPS control with INTER_REF_PIC_SET_PRED set and delta_idx_minus1 crafted to trigger the underflow.
Reject the entry early when the reference index would underflow.
Which versions are affected by CVE-2026-89882?
How do I fix CVE-2026-89882?
Apply the vendor's patch.
Is CVE-2026-89882 being exploited?
There is no known exploitation of CVE-2026-89882 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-89882, GHSA-w6ch-hfjf-3q38, UBUNTU-CVE-2026-89882.