CVE-2026-98812: Linux kernel · net/mctp: publish the mctp_dev only after it is initialised
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 5.6 Medium.
Data as of 28 Oct 2026, 04:12 UTC
CVSS:4.0/AV:L/AC:L/AT:P/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 18 Oct 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 ensures the mctp_dev device is published only after full initialization. Users should apply the official kernel updates that include this fix. No other mitigation or workaround is indicated.
Description
A vulnerability in the Linux kernel's net/mctp subsystem allows a null pointer dereference due to premature publication of the mctp_dev device before it is fully initialized. This can cause kernel address sanitizer (KASAN) null pointer dereference errors during certain socket operations. The issue is fixed by ensuring the mctp_dev object is published only after full initialization.
References
- ubuntu.com/security/CVE-2026-98812 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-98812 (opens in a new tab)
- git.kernel.org/stable/c/af6e4f931afc2d670d133aa2bedc8b6e3753c618 (opens in a new tab)
- git.kernel.org/stable/c/63120572edde85bb2b70b0ed4d4817ed52247613 (opens in a new tab)
- git.kernel.org/stable/c/aadf655e8ea9a8ffa24bb8d69f504572e8d18181 (opens in a new tab)
- git.kernel.org/stable/c/f37f42e6e039a48c2dcf6c079b9f7fbc864ab7ef (opens in a new tab)