CVE-2026-63876: Linux kernel · serial: zs: Convert to use a platform device
Affects Linux kernelSource GCVE Database
Not known to be exploited · fixed in 6.8.0-1066.69~22.04.1 : update Linux kernel when convenient.
Data as of 26 Oct 2026, 13:47 UTC
Rated by Threat Radar · No CVSS score from NVD or the CNA
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 12% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 6.8.0-1066.69~22.04.1, 6.8.0-1070.78~22.04.1, 6.8.0-1068.75~22.04.1 +36
Exploitation evidence
Disclosed: evidence found.
CVE published 20 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 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-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
An official fix is available and should be applied. The vulnerability is resolved by updating the Linux kernel to a version including the patch that converts the serial zs driver to use a platform device and updates resource handling accordingly. Users should upgrade to a patched kernel version as indicated in the vendor advisory.
Description
A vulnerability in the Linux kernel's serial zs driver was resolved by converting it to use a platform device. The issue involved a crash caused by dereferencing a pointer derived from a null pointer to the port's parent device during serial port initialization. The fix switches the driver to platform device usage, updates resource handling, and changes the driver probe method to prevent conflicts with other drivers sharing the same major device number. This change also affects the console handover timing during system bootstrap.
References
- ubuntu.com/security/CVE-2026-63876 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-63876 (opens in a new tab)
- git.kernel.org/linus/7cac59d08a73cb866ec51a483a6f3fe0f531947c (opens in a new tab)
- ubuntu.com/security/notices/USN-8593-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8603-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8618-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8663-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8664-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8903-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8905-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8906-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8904-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8903-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8905-2 (opens in a new tab)