CVE-2025-21968: Linux kernel · drm/amd/display: Fix slab-use-after-free on hdcp_work
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in 5.15.0-1086.93~20.04.1 : patch Linux kernel soon.
Data as of 12 Nov 2026, 19:27 UTC
- Patch
- Available – fixed in 5.15.0-1086.93~20.04.1, 5.15.0-1091.100~20.04.1, 5.15.0-1085.94~20.04.1 +64
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 1 Apr 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 12 Nov 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Patches and advisories
- ubuntu.com/security/notices/USN-7591-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7591-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7591-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7592-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7593-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7591-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-7597-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7597-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7598-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7602-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7605-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7606-1 (opens in a new tab)
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 24.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-azure-6.11pkg:deb/ubuntu/linux-azure-6.11?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-azure-nvidiapkg:deb/ubuntu/linux-azure-nvidia?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A patch is available and included in multiple fixed Linux kernel versions starting with 5.15.0-1086.93 and related releases. Users should apply the latest kernel updates provided by their distribution and reboot their systems to ensure the fix is applied. No additional mitigation steps are necessary beyond applying the official update.
Description
A slab-use-after-free vulnerability was identified and fixed in the AMD display driver component of the Linux kernel related to HDCP workqueue handling. The issue occurs when HDCP is destroyed but a delayed work queue is still running, leading to use-after-free conditions. This flaw has been addressed by cancelling the delayed work during workqueue destruction. The vulnerability affects multiple Linux kernel versions prior to fixed releases in the 5.15.x series and some earlier versions. The CVSS score is 7.8, indicating high severity with potential for confidentiality, integrity, and availability impacts. A patch is available and should be applied via standard system updates followed by a reboot.
References
- ubuntu.com/security/CVE-2025-21968 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-21968 (opens in a new tab)
- git.kernel.org/linus/e65e7bea220c3ce8c4c793b4ba35557f4994ab2b (opens in a new tab)
- ubuntu.com/security/notices/USN-7591-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7591-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7591-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7592-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7593-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7591-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-7597-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7597-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7598-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7602-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7605-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7606-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7591-5 (opens in a new tab)
- ubuntu.com/security/notices/USN-7605-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7628-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7591-6 (opens in a new tab)
- ubuntu.com/security/notices/USN-7655-1 (opens in a new tab)