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No exploitation reportedFix available

CVE-2021-47324

No exploitation reported by the sources we read.

  • Published2024-05-21
  • Fixed indc9403097be5 · c08a6b31e491 · b4ebf4a4692e · a397cb4576fc · 862f2b5a7c38 · 146cc288fb80
  • WeaknessCWE-416

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

In the Linux kernel, the following vulnerability has been resolved: watchdog: Fix possible use-after-free in wdt_startup() This module's remove path calls del_timer(). However, that function does not wait until the timer handler finishes. This means that the timer handler may still be running after the driver's remove function has finished, which would result in a use-after-free. Fix by calling del_timer_sync(), which makes sure the timer handler has finished, and unable to re-schedule itself.

Timeline

dates in UTC
  1. 2024-05-2115:15CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 UTC
Indicators tagged with this CVE, per day0 indicators over 7 days
Block these indicators
  • Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-47324?format=txt
  • CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-47324?format=csv
  • TAXII collection of exploited CVEs
  • The EDL and CSV take an API key on the Pro plan.

Versions per branch

CISA-ADP · NVD
Linux linux kernel
BranchAffectedFixed in
1+≥ 1da177e4c3f4, < dc9403097be5dc9403097be5
1+≥ 1da177e4c3f4, < c08a6b31e491c08a6b31e491
1+≥ 1da177e4c3f4, < b4ebf4a4692eb4ebf4a4692e
1+≥ 1da177e4c3f4, < a397cb4576fca397cb4576fc
862.x≥ 1da177e4c3f4, < 862f2b5a7c38862f2b5a7c38
146.x≥ 1da177e4c3f4, < 146cc288fb80146cc288fb80
63.x≥ 0 1da177e4c3f4, < 63a3dc24bd0563a3dc24bd05
8.x≥ 1da177e4c3f4, < 8adbbe6c86bb8adbbe6c86bb
5.13≥ 5.13, < 5.13.45.13.4
5.x≥ 5.11, < 5.12.195.12.19
5.x≥ 5.5, < 5.10.525.10.52
5.4≥ 4.20, < 5.4.1345.4.134

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

  1. Update Linux linux kernel to dc9403097be5 · c08a6b31e491 · b4ebf4a4692e · a397cb4576fc · 862f2b5a7c38 · 146cc288fb80 · 63a3dc24bd05 · 8adbbe6c86bb

Advisories and patches

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof-of-concept repositories
none listed
PoC-in-GitHub

Sources

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Published
2024-05-21
Last Modified
2026-06-17
NVD status
Analyzed

Frequently asked questions

What is CVE-2021-47324?

In the Linux kernel, the following vulnerability has been resolved: watchdog: Fix possible use-after-free in wdt_startup() This module's remove path calls del_timer(). However, that function does not wait until the timer handler finishes. This means that the timer handler may still be running after the driver's remove function has finished, which would result in a use-after-free. Fix by calling del_timer_sync(), which makes sure the timer handler has finished, and unable to re-schedule itself.

Is CVE-2021-47324 actively exploited?

Active exploitation of CVE-2021-47324 has not been confirmed. Its EPSS score was 1.2% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-47324?

CVE-2021-47324 has a CVSS v3 base score of 8.8 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

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