CVE-2026-63855 (CVSS 7.8)

Description

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu/vcn: set no_user_fence for VCN v2.5 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 efc9dd5590894109bce9a0bfe1fa5592dd6b20b1)

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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/2c6fb056567efb49f8674108b86088a1cfaa86d0 https://git.kernel.org/stable/c/4f317863a3ab212a027d8c8c3cc3af4e3fb95704 https://git.kernel.org/stable/c/5a3c6f76cab164a5d803084908d7050f649ab7f9 https://git.kernel.org/stable/c/602d4c5872b25ddd4d82fb2025efb9a05b187bb3 https://git.kernel.org/stable/c/8f0ea4524dc71c6c9ec97f2711f46e12f624140f

Frequently Asked Questions

What is CVE-2026-63855? +

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu/vcn: set no_user_fence for VCN v2.5 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 efc9dd5590894109bce9a0bfe1fa5592dd6b20b1) It has a CVSS v3.1 base score of 7.8 (HIGH).

How severe is CVE-2026-63855? +

CVE-2026-63855 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-2026-63855? +

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-2026-63855