CVE-2026-100079: Linux kernel · usb: typec: ucsi: unregister debugfs entries on teardown
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 5.5 Medium.
Data as of 26 Oct 2026, 13:47 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 1% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
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 25 Sep 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
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-gkepkg:deb/ubuntu/linux-gke?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 fix is available that properly unregisters debugfs entries during ucsi_unregister() and clears the debugfs pointer to prevent repeated unregister issues. Users should apply the updated Linux kernel versions that include this fix. No additional mitigation is required beyond applying the official patch.
Description
A vulnerability in the Linux kernel's USB Type-C UCSI driver was resolved. The issue involved debugfs entries created by ucsi_register() not being properly unregistered by ucsi_unregister(), causing conflicts when the same UCSI instance is unregistered and registered repeatedly. This could lead to errors and instability during remote processor restarts. The fix ensures debugfs entries are unregistered during ucsi_unregister() and clears related pointers to prevent repeated unregister issues.
References
- ubuntu.com/security/CVE-2026-100079 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-100079 (opens in a new tab)
- git.kernel.org/stable/c/fb7393519908befdc094be4ea913f582adbf2f7c (opens in a new tab)
- git.kernel.org/stable/c/7177c215e69658adbd2f2fc5b72e14be9208d2ba (opens in a new tab)
- git.kernel.org/stable/c/62efee351566321ad72a4abaf6eb7d972590585d (opens in a new tab)
- git.kernel.org/stable/c/eed73a65ab609b79d53de88cccc34b36dfe753c4 (opens in a new tab)
- git.kernel.org/stable/c/1f44d001620fd3caa30619a9bc73e9d15555408b (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-100079 (opens in a new tab)
- msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-100079.json (opens in a new tab)
- support.microsoft.com/lifecycle (opens in a new tab)
- first.org/cvss (opens in a new tab)