CVE-2026-97566: Linux kernel · mptcp: pm: kernel: drop pending ADD_ADDR when removing ID0
Affects Linux kernelSource GCVE Database
Not known to be exploited.
Data as of 26 Oct 2026, 13:47 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 10% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Exploitation 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 has been implemented to address this issue by making the ID0 removal path symmetric with the non-zero ID path, ensuring proper cleanup of pending ADD_ADDR announcements. Users should apply the available kernel updates that include this patch to remediate the vulnerability.
Description
A vulnerability in the Linux kernel's Multipath TCP (MPTCP) path manager was resolved. The issue involved stale ADD_ADDR announcement entries remaining when removing the ID0 endpoint due to asymmetry in cleanup paths. This could cause kernel warnings during path reselection. The fix ensures symmetric cleanup for ID0 removal by properly removing pending announcements and adjusting signaling counts.
References
- ubuntu.com/security/CVE-2026-97566 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-97566 (opens in a new tab)
- git.kernel.org/stable/c/d4a67a880654e1bfe318a31bea0bdbb026a09ade (opens in a new tab)
- git.kernel.org/stable/c/545616b4e7325be3c61fc082538cb06d14f7b1db (opens in a new tab)
- git.kernel.org/stable/c/2ac7d6e620764f1fc79eb4edd3610a7a661981ca (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-97566 (opens in a new tab)
- git.kernel.org/stable/c/bacf23e7c9876c9f4170166b3597cb22ea3ed39b (opens in a new tab)