CVE-2026-93288: Linux kernel · netfilter: nfnetlink_log: wait for rcu grace period before freeing pernet state
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 2% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 24 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 is available that modifies the nfnetlink_log code to wait for the RCU grace period before freeing pernet state. Users should apply the official Linux kernel updates that include this patch to resolve the issue. No additional mitigations are indicated by the vendor advisory.
Description
A vulnerability in the Linux kernel's netfilter nfnetlink_log component was resolved. The issue involved freeing per-network namespace state without waiting for an RCU grace period, potentially causing use-after-free conditions during concurrent packet processing. The fix ensures the pointer is cleared only after RCU readers have completed, preventing unsafe memory access.
References
- ubuntu.com/security/CVE-2026-93288 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-93288 (opens in a new tab)
- git.kernel.org/stable/c/33d1469b0124cc0baaea7a2032123b77a81e0940 (opens in a new tab)
- git.kernel.org/stable/c/dc20050b6b12ca58066715d088e1a537535d938d (opens in a new tab)
- git.kernel.org/stable/c/f4461654374576e9d5d0245fd534c46ad8509051 (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-93288 (opens in a new tab)
- git.kernel.org/stable/c/3b9aa62d78ce80de47af2db472ff452398755213 (opens in a new tab)
- git.kernel.org/stable/c/5570d6c8b320dbcc602617ee08c27ce752fed65a (opens in a new tab)
- git.kernel.org/stable/c/ba2e246aa294f9acd86194ea87fb6834ed0a37ac (opens in a new tab)