CVE-2021-46993
sched: Fix out-of-bound access in uclamp
Description
In the Linux kernel, the following vulnerability has been resolved: sched: Fix out-of-bound access in uclamp Util-clamp places tasks in different buckets based on their clamp values for performance reasons. However, the size of buckets is currently computed using a rounding division, which can lead to an off-by-one error in some configurations. For instance, with 20 buckets, the bucket size will be 1024/20=51. A task with a clamp of 1024 will be mapped to bucket id 1024/51=20. Sadly, correct indexes are in range [0,19], hence leading to an out of bound memory access. Clamp the bucket id to fix the issue.
INFO
Published Date :
Feb. 28, 2024, 9:15 a.m.
Last Modified :
Dec. 24, 2024, 2:40 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 | HIGH | [email protected] |
Solution
- Update the kernel to a patched version.
- 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-2021-46993.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-46993 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-2021-46993
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-2021-46993 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-46993 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]
Dec. 24, 2024
Action Type Old Value New Value Added CVSS V3.1 NIST AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H Added CWE NIST CWE-125 Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.3 up to (excluding) 5.4.120 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.5 up to (excluding) 5.10.38 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.11 up to (excluding) 5.11.22 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.12 up to (excluding) 5.12.5 Changed Reference Type https://git.kernel.org/stable/c/3da3f804b82a0a382d523a21acf4cf3bb35f936d No Types Assigned https://git.kernel.org/stable/c/3da3f804b82a0a382d523a21acf4cf3bb35f936d Patch Changed Reference Type https://git.kernel.org/stable/c/3da3f804b82a0a382d523a21acf4cf3bb35f936d No Types Assigned https://git.kernel.org/stable/c/3da3f804b82a0a382d523a21acf4cf3bb35f936d Patch Changed Reference Type https://git.kernel.org/stable/c/42ee47c7e3569d9a0e2cb5053c496d97d380472f No Types Assigned https://git.kernel.org/stable/c/42ee47c7e3569d9a0e2cb5053c496d97d380472f Patch Changed Reference Type https://git.kernel.org/stable/c/42ee47c7e3569d9a0e2cb5053c496d97d380472f No Types Assigned https://git.kernel.org/stable/c/42ee47c7e3569d9a0e2cb5053c496d97d380472f Patch Changed Reference Type https://git.kernel.org/stable/c/687f523c134b7f0bd040ee1230f6d17990d54172 No Types Assigned https://git.kernel.org/stable/c/687f523c134b7f0bd040ee1230f6d17990d54172 Patch Changed Reference Type https://git.kernel.org/stable/c/687f523c134b7f0bd040ee1230f6d17990d54172 No Types Assigned https://git.kernel.org/stable/c/687f523c134b7f0bd040ee1230f6d17990d54172 Patch Changed Reference Type https://git.kernel.org/stable/c/6d2f8909a5fabb73fe2a63918117943986c39b6c No Types Assigned https://git.kernel.org/stable/c/6d2f8909a5fabb73fe2a63918117943986c39b6c Patch Changed Reference Type https://git.kernel.org/stable/c/6d2f8909a5fabb73fe2a63918117943986c39b6c No Types Assigned https://git.kernel.org/stable/c/6d2f8909a5fabb73fe2a63918117943986c39b6c Patch Changed Reference Type https://git.kernel.org/stable/c/f7347c85490b92dd144fa1fba9e1eca501656ab3 No Types Assigned https://git.kernel.org/stable/c/f7347c85490b92dd144fa1fba9e1eca501656ab3 Patch Changed Reference Type https://git.kernel.org/stable/c/f7347c85490b92dd144fa1fba9e1eca501656ab3 No Types Assigned https://git.kernel.org/stable/c/f7347c85490b92dd144fa1fba9e1eca501656ab3 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/3da3f804b82a0a382d523a21acf4cf3bb35f936d Added Reference https://git.kernel.org/stable/c/42ee47c7e3569d9a0e2cb5053c496d97d380472f Added Reference https://git.kernel.org/stable/c/687f523c134b7f0bd040ee1230f6d17990d54172 Added Reference https://git.kernel.org/stable/c/6d2f8909a5fabb73fe2a63918117943986c39b6c Added Reference https://git.kernel.org/stable/c/f7347c85490b92dd144fa1fba9e1eca501656ab3 -
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. 28, 2024
Action Type Old Value New Value Added Description In the Linux kernel, the following vulnerability has been resolved: sched: Fix out-of-bound access in uclamp Util-clamp places tasks in different buckets based on their clamp values for performance reasons. However, the size of buckets is currently computed using a rounding division, which can lead to an off-by-one error in some configurations. For instance, with 20 buckets, the bucket size will be 1024/20=51. A task with a clamp of 1024 will be mapped to bucket id 1024/51=20. Sadly, correct indexes are in range [0,19], hence leading to an out of bound memory access. Clamp the bucket id to fix the issue. Added Reference Linux https://git.kernel.org/stable/c/687f523c134b7f0bd040ee1230f6d17990d54172 [No types assigned] Added Reference Linux https://git.kernel.org/stable/c/f7347c85490b92dd144fa1fba9e1eca501656ab3 [No types assigned] Added Reference Linux https://git.kernel.org/stable/c/3da3f804b82a0a382d523a21acf4cf3bb35f936d [No types assigned] Added Reference Linux https://git.kernel.org/stable/c/42ee47c7e3569d9a0e2cb5053c496d97d380472f [No types assigned] Added Reference Linux https://git.kernel.org/stable/c/6d2f8909a5fabb73fe2a63918117943986c39b6c [No types assigned]