CVE-2026-72322: Linux kernel · ipv6: mcast: Fix potential UAF in MLD delayed work
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 9.8 Critical · fixed in 5.15.0-1117.124~20.04.1 : patch Linux kernel as a priority.
Data as of 28 Oct 2026, 02:49 UTC
- 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 +57
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 15 Aug 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.
Patches and advisories
- ubuntu.com/security/notices/USN-8781-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8816-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8816-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8816-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8816-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8876-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8878-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8879-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8877-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8875-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8888-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8888-2 (opens in a new tab)
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 patch is available and should be applied promptly. The vulnerability is fixed in Linux kernel versions 5.15.0-1117.124~20.04.1 and later as listed. Users should upgrade to these fixed versions to mitigate the issue. No additional mitigation is required beyond applying the official kernel updates.
Description
A critical use-after-free vulnerability (CVE-2026-72322) exists in the IPv6 multicast listener discovery (MLD) delayed work handling in the Linux kernel. The flaw arises from a race condition between device teardown and incoming MLD query processing, which can cause kernel memory to be accessed after it has been freed, leading to a kernel panic. The issue is fixed by ensuring references are only acquired if the device is not already being destroyed. Multiple Linux kernel versions prior to 5.15.0-1117.124~20.04.1 and related versions are affected. A patch is available and should be applied to mitigate this vulnerability.
References
- ubuntu.com/security/CVE-2026-72322 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-72322 (opens in a new tab)
- git.kernel.org/linus/9b26518b6896a16b809b1e42986f4ebac7bccc1e (opens in a new tab)
- git.kernel.org/stable/c/0401d6cf7877c9be36652385dfcbf7f891b8b590 (opens in a new tab)
- git.kernel.org/stable/c/0458ba1cda830ba4ccfcd9e19c0891438bcdbe4e (opens in a new tab)
- git.kernel.org/stable/c/9815e834f5ff8b39e0ea9f0dbd532f4a3b8f0785 (opens in a new tab)
- git.kernel.org/stable/c/9b26518b6896a16b809b1e42986f4ebac7bccc1e (opens in a new tab)
- git.kernel.org/stable/c/9ce741c22df4fd9546e30306317ac7df3607e48f (opens in a new tab)
- git.kernel.org/stable/c/ebbebf6cee950d7f1c81990256c0eae9e62572ae (opens in a new tab)
- git.kernel.org/stable/c/f03b0a45535d49bdab7e502efaacee205b2a7865 (opens in a new tab)
- git.kernel.org/stable/c/f12b63ef26a035c5a29b3ef56401e38199010d4a (opens in a new tab)
- ubuntu.com/security/notices/USN-8781-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8816-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8816-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8816-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8816-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8876-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8878-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8879-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8877-1 (opens in a new tab)