CVE-2026-53000: Linux kernel · netfilter: nat: use kfree_rcu to release ops
Affects Linux kernelSource CVE Database V5
Not known to be exploited · CVSS 7.8 High · fixed in ede973d62d26d9c550269af05366ab9e30fc92ee : patch Linux kernel soon.
Data as of 26 Oct 2026, 13:47 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 7% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Total control over the software or total information disclosure
CISA SSVC assessment, 2026-10-16.
- Patch
- Available – fixed in ede973d62d26d9c550269af05366ab9e30fc92ee, 050f98e56782b14677c5bae50800e60775bbf6bb, 32fdd2e38e7435a368d88f5977a7d6585ebc8b0e +2
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 Jun 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 |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in– |
Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: nat: use kfree_rcu to release ops Florian Westphal says: "Historically this is not an issue, even for normal base hooks: the data path doesn't use the original nf_hook_ops that are used to register the callbacks. However, in v5.14 I added the ability to dump the active netfilter hooks from userspace. This code will peek back into the nf_hook_ops that are available at the tail of the pointer-array blob used by the datapath. The nat hooks are special, because they are called indirectly from the central nat dispatcher hook. They are currently invisible to the nfnl hook dump subsystem though. But once that changes the nat ops structures have to be deferred too." Update nf_nat_register_fn() to deal with partial exposition of the hooks from error path which can be also an issue for nfnetlink_hook.
References
- git.kernel.org/stable/c/ede973d62d26d9c550269af05366ab9e30fc92ee (opens in a new tab)
- git.kernel.org/stable/c/050f98e56782b14677c5bae50800e60775bbf6bb (opens in a new tab)
- git.kernel.org/stable/c/32fdd2e38e7435a368d88f5977a7d6585ebc8b0e (opens in a new tab)
- git.kernel.org/stable/c/3c7511f38ab511b791196b13ae48bf4973bf7dfd (opens in a new tab)
- git.kernel.org/stable/c/6eda0d771f94267f73f57c94630aa47e90957915 (opens in a new tab)
- access.redhat.com/security/cve/CVE-2026-53000 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2492273 (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-53000.json (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:55445 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:68100 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:67720 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:64808 (opens in a new tab)