CVE-2026-63856 (CVSS 7.8)

Description

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu/vcn: set no_user_fence for VCN v2.0 enc/dec rings VCN encoder and decoder rings do not support 64-bit user fence writes, reject CS submissions with user fences. (cherry picked from commit e2b5499fca55f1a32960a311bbb62e35891eaf73)

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CVSS v3.1 Score

7.8

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS — Exploit Prediction

0.0012

Probability of exploitation

0.02%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

References

Other References

https://git.kernel.org/stable/c/5e777bc4cbe928ac0fd95e368fee1540f2ce4db2 https://git.kernel.org/stable/c/8d80b293b41fcb5e9396db93e788b0f4ebcbafb7 https://git.kernel.org/stable/c/ac06ce5cac9e711281585d09d00c6efcd9b86396 https://git.kernel.org/stable/c/c71aecae98e42dcf2baf462df50b3a2cf1a93fe4 https://git.kernel.org/stable/c/f264019be80de79f84f464846451445923bffea0

Frequently Asked Questions

What is CVE-2026-63856? +

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu/vcn: set no_user_fence for VCN v2.0 enc/dec rings VCN encoder and decoder rings do not support 64-bit user fence writes, reject CS submissions with user fences. (cherry picked from commit e2b5499fca55f1a32960a311bbb62e35891eaf73) It has a CVSS v3.1 base score of 7.8 (HIGH).

How severe is CVE-2026-63856? +

CVE-2026-63856 has a CVSS v3.1 score of 7.8 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0012, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-63856? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

CVE-2026-63856