CVE-2026-72493: Linux kernel · net: serialize netif_running() check in enqueue_to_backlog()
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 9.9 Critical · fixed in 7.0.0-1013.13~24.04.1 : patch Linux kernel as a priority.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 34% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 7.0.0-1013.13~24.04.1, 7.0.0-1017.17~24.04.1, 7.0.0-1016.16~24.04.1 +12
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/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.
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 by updating the Linux kernel to the fixed versions provided by the vendor. The Ubuntu advisory USN-8816-1 confirms the availability of fixes in multiple kernel packages. After updating, a system reboot is required. Due to ABI changes, recompilation and reinstallation of third-party kernel modules may be necessary. No additional mitigations are indicated beyond applying the official patch.
Description
A race condition vulnerability in the Linux kernel's network subsystem was resolved, involving a use-after-free (UAF) triggered by improper serialization of the netif_running() check in enqueue_to_backlog(). This flaw allowed packets to escape backlog flushing during device unregistration, potentially leading to memory corruption. The issue was fixed by moving the netif_running() check inside the backlog lock to serialize access and prevent the race condition. Multiple specific Linux kernel versions are affected. A high-severity CVSS 3.1 score of 9.9 reflects the critical impact of this vulnerability. Official patches are available and should be applied promptly.
References
- nvd.nist.gov/vuln/detail/CVE-2026-72493 (opens in a new tab)
- git.kernel.org/stable/c/2fface6e0bbd6314d1d9d071abf2c4d67548511c (opens in a new tab)
- git.kernel.org/stable/c/46762cefe7f4e5bffc1eb467810a7bbb02e461d7 (opens in a new tab)
- ubuntu.com/security/CVE-2026-72493 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-72493 (opens in a new tab)
- git.kernel.org/linus/46762cefe7f4e5bffc1eb467810a7bbb02e461d7 (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-8888-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8888-2 (opens in a new tab)