CVE-2026-63851: Linux kernel · drm/amdgpu/vcn: set no_user_fence for VCN v4.0.5 enc ring
Source GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in 75091030f07b7957cc0646cd52e2d9d15f611483 : patch Linux kernel soon.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 6% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 75091030f07b7957cc0646cd52e2d9d15f611483, 589a254bf3e88204c8402b9cbccd5e23a0af990f, 7f23b5c420b9f68a210c29c5123bace670aa8cc9 +1
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 19 Jul 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade Linux kernel to 75091030f07b7957cc0646cd52e2d9d15f611483, 589a254bf3e88204c8402b9cbccd5e23a0af990f, 7f23b5c420b9f68a210c29c5123bace670aa8cc9 or 6d9a98c5ed65ba92a09e4ca5a5f6941448145529.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in– |
AI-suggested
A fix has been applied in the Linux kernel by setting the no_user_fence flag for the VCN v4.0.5 encoder and decoder rings to reject command submissions with user fences. Users should update their Linux kernel to a version that includes this commit to mitigate the vulnerability. Patch status is confirmed by the kernel commit referenced. No additional mitigation steps are indicated.
Description
In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu/vcn: set no_user_fence for VCN v4.0.5 enc ring VCN encoder and decoder rings do not support 64-bit user fence writes, reject CS submissions with user fences. (cherry picked from commit 084d94ac93707bdda07efb5cee786f632de4219b)
References
- nvd.nist.gov/vuln/detail/CVE-2026-63851 (opens in a new tab)
- git.kernel.org/stable/c/589a254bf3e88204c8402b9cbccd5e23a0af990f (opens in a new tab)
- git.kernel.org/stable/c/6d9a98c5ed65ba92a09e4ca5a5f6941448145529 (opens in a new tab)
- git.kernel.org/stable/c/75091030f07b7957cc0646cd52e2d9d15f611483 (opens in a new tab)
- git.kernel.org/stable/c/7f23b5c420b9f68a210c29c5123bace670aa8cc9 (opens in a new tab)