CVE-2021-46971
Linux Kernel Perf SELinux Locked Down Information Disclosure Vulnerability
Description
In the Linux kernel, the following vulnerability has been resolved: perf/core: Fix unconditional security_locked_down() call Currently, the lockdown state is queried unconditionally, even though its result is used only if the PERF_SAMPLE_REGS_INTR bit is set in attr.sample_type. While that doesn't matter in case of the Lockdown LSM, it causes trouble with the SELinux's lockdown hook implementation. SELinux implements the locked_down hook with a check whether the current task's type has the corresponding "lockdown" class permission ("integrity" or "confidentiality") allowed in the policy. This means that calling the hook when the access control decision would be ignored generates a bogus permission check and audit record. Fix this by checking sample_type first and only calling the hook when its result would be honored.
INFO
Published Date :
Feb. 27, 2024, 7:04 p.m.
Last Modified :
Jan. 8, 2025, 5:26 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | LOW | [email protected] |
Solution
- Update affected Linux kernel packages.
- Reboot the system to apply the update.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2021-46971.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-46971 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2021-46971
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2021-46971 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-46971 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Jan. 08, 2025
Action Type Old Value New Value Added CVSS V3.1 NIST AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N Added CWE NIST NVD-CWE-noinfo Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.4 up to (excluding) 5.4.117 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.5 up to (excluding) 5.10.35 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.11 up to (excluding) 5.11.19 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.12 up to (excluding) 5.12.2 Changed Reference Type https://git.kernel.org/stable/c/08ef1af4de5fe7de9c6d69f1e22e51b66e385d9b No Types Assigned https://git.kernel.org/stable/c/08ef1af4de5fe7de9c6d69f1e22e51b66e385d9b Patch Changed Reference Type https://git.kernel.org/stable/c/08ef1af4de5fe7de9c6d69f1e22e51b66e385d9b No Types Assigned https://git.kernel.org/stable/c/08ef1af4de5fe7de9c6d69f1e22e51b66e385d9b Patch Changed Reference Type https://git.kernel.org/stable/c/4348d3b5027bc3ff6336368b6c60605d4ef8e1ce No Types Assigned https://git.kernel.org/stable/c/4348d3b5027bc3ff6336368b6c60605d4ef8e1ce Patch Changed Reference Type https://git.kernel.org/stable/c/4348d3b5027bc3ff6336368b6c60605d4ef8e1ce No Types Assigned https://git.kernel.org/stable/c/4348d3b5027bc3ff6336368b6c60605d4ef8e1ce Patch Changed Reference Type https://git.kernel.org/stable/c/b246759284d6a2bc5b6f1009caeeb3abce2ec9ff No Types Assigned https://git.kernel.org/stable/c/b246759284d6a2bc5b6f1009caeeb3abce2ec9ff Patch Changed Reference Type https://git.kernel.org/stable/c/b246759284d6a2bc5b6f1009caeeb3abce2ec9ff No Types Assigned https://git.kernel.org/stable/c/b246759284d6a2bc5b6f1009caeeb3abce2ec9ff Patch Changed Reference Type https://git.kernel.org/stable/c/c7b0208ee370b89d20486fae71cd9abb759819c1 No Types Assigned https://git.kernel.org/stable/c/c7b0208ee370b89d20486fae71cd9abb759819c1 Patch Changed Reference Type https://git.kernel.org/stable/c/c7b0208ee370b89d20486fae71cd9abb759819c1 No Types Assigned https://git.kernel.org/stable/c/c7b0208ee370b89d20486fae71cd9abb759819c1 Patch Changed Reference Type https://git.kernel.org/stable/c/f5809ca4c311b71bfaba6d13f4e39eab0557895e No Types Assigned https://git.kernel.org/stable/c/f5809ca4c311b71bfaba6d13f4e39eab0557895e Patch Changed Reference Type https://git.kernel.org/stable/c/f5809ca4c311b71bfaba6d13f4e39eab0557895e No Types Assigned https://git.kernel.org/stable/c/f5809ca4c311b71bfaba6d13f4e39eab0557895e Patch -
CVE Modified by af854a3a-2127-422b-91ae-364da2661108
Nov. 21, 2024
Action Type Old Value New Value Added Reference https://git.kernel.org/stable/c/08ef1af4de5fe7de9c6d69f1e22e51b66e385d9b Added Reference https://git.kernel.org/stable/c/4348d3b5027bc3ff6336368b6c60605d4ef8e1ce Added Reference https://git.kernel.org/stable/c/b246759284d6a2bc5b6f1009caeeb3abce2ec9ff Added Reference https://git.kernel.org/stable/c/c7b0208ee370b89d20486fae71cd9abb759819c1 Added Reference https://git.kernel.org/stable/c/f5809ca4c311b71bfaba6d13f4e39eab0557895e -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
May. 28, 2024
Action Type Old Value New Value -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
May. 14, 2024
Action Type Old Value New Value -
CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Feb. 27, 2024
Action Type Old Value New Value Added Description In the Linux kernel, the following vulnerability has been resolved: perf/core: Fix unconditional security_locked_down() call Currently, the lockdown state is queried unconditionally, even though its result is used only if the PERF_SAMPLE_REGS_INTR bit is set in attr.sample_type. While that doesn't matter in case of the Lockdown LSM, it causes trouble with the SELinux's lockdown hook implementation. SELinux implements the locked_down hook with a check whether the current task's type has the corresponding "lockdown" class permission ("integrity" or "confidentiality") allowed in the policy. This means that calling the hook when the access control decision would be ignored generates a bogus permission check and audit record. Fix this by checking sample_type first and only calling the hook when its result would be honored. Added Reference Linux https://git.kernel.org/stable/c/b246759284d6a2bc5b6f1009caeeb3abce2ec9ff [No types assigned] Added Reference Linux https://git.kernel.org/stable/c/4348d3b5027bc3ff6336368b6c60605d4ef8e1ce [No types assigned] Added Reference Linux https://git.kernel.org/stable/c/f5809ca4c311b71bfaba6d13f4e39eab0557895e [No types assigned] Added Reference Linux https://git.kernel.org/stable/c/c7b0208ee370b89d20486fae71cd9abb759819c1 [No types assigned] Added Reference Linux https://git.kernel.org/stable/c/08ef1af4de5fe7de9c6d69f1e22e51b66e385d9b [No types assigned]