CVE-2025-21943: Linux kernel · gpio: aggregator: protect driver attr handlers against module unload
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 4.7 Medium · fixed in 5.15.0-1084.91~20.04.1 : update Linux kernel when convenient.
Data as of 12 Nov 2026, 19:33 UTC
- Patch
- Available – fixed in 5.15.0-1084.91~20.04.1, 5.15.0-1089.98~20.04.1, 5.15.0-1083.92~20.04.1 +64
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/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-7510-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7510-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7511-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7511-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7512-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7510-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7510-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-7510-5 (opens in a new tab)
- ubuntu.com/security/notices/USN-7511-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7510-6 (opens in a new tab)
- ubuntu.com/security/notices/USN-7510-7 (opens in a new tab)
- ubuntu.com/security/notices/USN-7510-8 (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 Linux kernel versions 5.15.0-1076.79~20.04.1 and later. Users should update to these fixed kernel versions or later to remediate this issue. After applying the update, a system reboot is required to ensure the fix is active. No additional mitigation actions are necessary as the patch fully addresses the vulnerability.
Description
CVE-2025-21943 is a vulnerability in the Linux kernel's gpio-aggregator driver where driver attribute handlers did not properly protect against module unload race conditions. This could lead to system instability and kernel warnings due to dangling platform devices and corrupted kernel lists. The issue is resolved by adding reference counting to prevent module unload during critical operations.
References
- ubuntu.com/security/CVE-2025-21943 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-21943 (opens in a new tab)
- git.kernel.org/linus/12f65d1203507f7db3ba59930fe29a3b8eee9945 (opens in a new tab)
- ubuntu.com/security/notices/USN-7510-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7510-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7511-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7511-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7512-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7510-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7510-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-7510-5 (opens in a new tab)
- ubuntu.com/security/notices/USN-7511-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7510-6 (opens in a new tab)
- ubuntu.com/security/notices/USN-7510-7 (opens in a new tab)
- ubuntu.com/security/notices/USN-7510-8 (opens in a new tab)
- ubuntu.com/security/notices/USN-7593-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7595-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7596-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7595-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7596-2 (opens in a new tab)