CVE-2026-68206 media: v4l2-ctrls: validate HEVC active reference counts
Missing validation of HEVC reference counts in the Linux kernel media subsystem can lead to driver instability or crashes.
- 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-2026-68206?
CVE-2026-68206 is a high-severity vulnerability in Linux, published on 10 Aug 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: v4l2-ctrls: validate HEVC active reference counts
HEVC slice parameters are shared stateless V4L2 controls, but the common validation path does not verify the active L0/L1 reference counts before driver-specific code consumes them.
The original report came from Cedrus, but the active count bounds are not Cedrus-specific. Validate them in the common HEVC slice control path so stateless HEVC drivers get the same basic guarantees as soon as the control is queued.
Do not reject ref_idx_l0/ref_idx_l1 entries here. Existing userspace may use out-of-range sentinel values such as 0xff for missing references, and some hardware can use that information for concealment. Keep this common check limited to the active reference counts.
Weakness: CWE-20
Which versions are affected by CVE-2026-68206?
How do I fix CVE-2026-68206?
Apply the vendor's patch.
Is CVE-2026-68206 being exploited?
There is no known exploitation of CVE-2026-68206 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-68206, DEBIAN-CVE-2026-68206, GHSA-qx89-rcg9-ghw4, UBUNTU-CVE-2026-68206.