CVE-2021-46971

Bogus audit records via unconditional lockdown check

Published Feb 27, 2024 · Updated May 11, 2026

Access-control error in Linux kernels allows local users to trigger bogus SELinux permission checks and audit records through perf events. In kernel/events/core.c, perf_event_open calls security_locked_down unconditionally when attr.sample_type omits PERF_SAMPLE_REGS_INTR and the returned decision cannot affect the request. The effect requires SELinux's lockdown hook and low-privileged local access, and it pollutes security-policy auditing rather than exposing data or interrupting the host.

CVSS severity3.3
Low
EPSS probability0.23%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Access-control error in Linux kernels allows local users to trigger bogus SELinux permission checks and audit records through perf events. In kernel/events/core.c, perf_event_open calls security_locked_down unconditionally when attr.sample_type omits PERF_SAMPLE_REGS_INTR and the returned decision cannot affect the request. The effect requires SELinux's lockdown hook and low-privileged local access, and it pollutes security-policy auditing rather than exposing data or interrupting the host.

The record

CVE
CVE-2021-46971
Published
Feb 27, 2024
Updated
May 11, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
Unavailable
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 27, 2024CVE publishedPublication date reported by the CVE source.
  2. May 11, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=5.4
  2. Affected versionversion=b0c8fdc7fdb77586c3d1937050925b960743306e <08ef1af4de5fe7de9c6d69f1e22e51b66e385d9b
  3. Affected versionversion=b0c8fdc7fdb77586c3d1937050925b960743306e <4348d3b5027bc3ff6336368b6c60605d4ef8e1ce
  4. Affected versionversion=b0c8fdc7fdb77586c3d1937050925b960743306e <b246759284d6a2bc5b6f1009caeeb3abce2ec9ff
  5. Affected versionversion=b0c8fdc7fdb77586c3d1937050925b960743306e <c7b0208ee370b89d20486fae71cd9abb759819c1
  6. Affected versionversion=b0c8fdc7fdb77586c3d1937050925b960743306e <f5809ca4c311b71bfaba6d13f4e39eab0557895e

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=5.4; version=b0c8fdc7fdb77586c3d1937050925b960743306e <08ef1af4de5fe7de9c6d69f1e22e51b66e385d9b; version=b0c8fdc7fdb77586c3d1937050925b960743306e <4348d3b5027bc3ff6336368b6c60605d4ef8e1ce; version=b0c8fdc7fdb77586c3d1937050925b960743306e <b246759284d6a2bc5b6f1009caeeb3abce2ec9ff; version=b0c8fdc7fdb77586c3d1937050925b960743306e <c7b0208ee370b89d20486fae71cd9abb759819c1; version=b0c8fdc7fdb77586c3d1937050925b960743306e <f5809ca4c311b71bfaba6d13f4e39eab0557895e

Published CVSS scores

3.3NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo