CVE-2026-46021: Linux kernel · thermal: core: Fix thermal zone governor cleanup issues
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 5.5 Medium · fixed in 5.15.0-1117.124~20.04.1 : update Linux kernel when convenient.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 3% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.15.0-1117.124~20.04.1, 5.15.0-1123.132~20.04.1, 5.15.0-1122.131~20.04.1 +69
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 27 May 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 to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-ibmpkg:deb/ubuntu/linux-ibm?arch=source&distro=resoluteOther 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 should be applied to affected Linux kernel versions. The vendor advisory from Ubuntu confirms that this issue has been fixed. Users should update their linux-aws kernel packages to the fixed versions to remediate this vulnerability.
Description
A vulnerability in the Linux kernel thermal subsystem was fixed that involved improper cleanup of thermal zone governors. If thermal_zone_device_register_with_trips() fails after adding a thermal governor, the governor may not be removed properly, causing a memory leak. Additionally, thermal_zone_device_unregister() could call thermal_set_governor() without locking, leading to a race condition and potential use-after-free. These issues were addressed by adding calls to thermal_set_governor() to ensure proper cleanup and locking.
References
- ubuntu.com/security/CVE-2026-46021 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-46021 (opens in a new tab)
- git.kernel.org/linus/41ff66baf81c6541f4f985dd7eac4494d03d9440 (opens in a new tab)
- ubuntu.com/security/notices/USN-8488-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8489-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8488-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8507-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8569-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8567-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8574-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8574-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8595-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8596-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8603-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8595-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8606-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8607-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8608-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8609-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8574-3 (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-46021 (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-019113.html (opens in a new tab)
- git.kernel.org/stable/c/37a430a2d4e66ec8238da6c7f7e48809bf265e13 (opens in a new tab)
- git.kernel.org/stable/c/41ff66baf81c6541f4f985dd7eac4494d03d9440 (opens in a new tab)
- git.kernel.org/stable/c/64d4ebf91d082034bbc5ae3ba2d7fd800bc02d06 (opens in a new tab)
- git.kernel.org/stable/c/75f8f3c3e09122270986de9d7aa347d701676761 (opens in a new tab)
- git.kernel.org/stable/c/8e563d8db50f303171aceb79eec0807e7ba06951 (opens in a new tab)
- git.kernel.org/stable/c/a172fa18bc370b776ac1510abb0dcb50a7a35fac (opens in a new tab)
- git.kernel.org/stable/c/d4eb861adde5ce22e459fbd29366f47bb2167977 (opens in a new tab)
- git.kernel.org/stable/c/f412e541d25a3dfaf3d53e012ade6ff03cae8a45 (opens in a new tab)