Skip to content
VulniPulse
Advisory severityMedium4.7Red Hat Linux

Medium [CVE-2026-64079] allocate hook ops while under mutex

This medium-severity Red Hat Linux advisory covers CVE-2026-64079 affecting Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 9.

Aggregated and source-linked by VulniPulse. Data sources, validation and limitations.

CVE-2026-64079 Source published Source updated

VulniPulse record published Record updated

CVE-2026-64079
Affected products & platforms
Red Hat LinuxLinux Kernel
Open source advisory

Get an email when Red Hat Linux Linux Kernel publishes the next one.

See Red Hat Linux Linux Kernel's last 90 days of advisories first. Then choose one product with live alerts free for life, or a free month of real-time alerts on everything with the severity, the fixed version and the vendor's link (card needed, then US$15/month; we email you before the first charge).

Alert me about Red Hat Linux Linux Kernel

Summary

In the Linux kernel, the following vulnerability has been resolved: netfilter: x_tables: allocate hook ops while under mutex arp/ip(6)t_register_table() add the table to the per-netns list via xt_register_table() before allocating the per-netns hook ops copy via kmemdup_array(). This leaves a window where the table is visible in the list with ops=NULL.

Also ensure the table is no longer processing packets before its torn down on error unwind. nf_register_net_hooks might have published at least one hook; call synchronize_rcu() if there was an error. audit log register message gets deferred until all operations have passed, this avoids need to emit another ureg message in case of error unwinding.

Based on earlier patch by Tristan Madani. A race condition occurs when a network namespace (netns) table is registered, making it visible with a null operations (ops) pointer.

If a pernet exit operation runs concurrently, it can attempt to unregister the table using this null pointer, leading to a null dereference. This vulnerability can be exploited by a local attacker to cause a Denial of Service (DoS) by crashing the system.

A concurrent pernet exit path can find that table and pass a NULL ops pointer to nf_unregister_net_hooks, causing a NULL pointer dereference and kernel crash.

Affected versions

No affected-version range was extracted from the source record. The vendor advisory is authoritative. Check it before change work.

Official advisory · high-confidence parse· fetched 6 days ago·verify at source

Fixed versions

No fixed release is recorded yet. That does not prove no patch exists. Confirm against the vendor advisory.

Official advisory · high-confidence parse· fetched 6 days ago·verify at source

Mitigation checklist

Recommended fix / mitigation
  • Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.

Official advisory · high-confidence parse· fetched 6 days ago·verify at source

All Red Hat Linux advisories

iPhone and Android apps · New on the App Store

Monitor future Red Hat Linux CVEs from your phone.

Choose a whole vendor or a precise platform, then receive matching security advisories by phone notification, email, or both. Coverage follows 34 official vendor sources and 160+ reviewed platform categories.

Discussion(0)

No comments yet. Share field notes, upgrade gotchas, or questions — verify against the vendor advisory before acting on community advice.

Sign in to join the discussion.