{"cve":"CVE-2021-47321","nvd":{"published":"2024-05-21T15:15:19.297","modified":"2026-06-17T04:17:11.387","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nwatchdog: Fix possible use-after-free by calling del_timer_sync()\n\nThis driver's remove path calls del_timer(). However, that function\ndoes not wait until the timer handler finishes. This means that the\ntimer handler may still be running after the driver's remove function\nhas finished, which would result in a use-after-free.\n\nFix by calling del_timer_sync(), which makes sure the timer handler\nhas finished, and unable to re-schedule itself.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":["CWE-416"],"references":["https://git.kernel.org/stable/c/1a053c4d716898a53c2e31c574a70ea0c37044a3","https://git.kernel.org/stable/c/4c05dac488a660fe2925c047ecb119e7afaaeb1e","https://git.kernel.org/stable/c/58606882ad8ec6c39e0f40344b922921ef94ab4d","https://git.kernel.org/stable/c/66ba9cf929b1c4fabf545bd4c18f6f64e23e46e4","https://git.kernel.org/stable/c/8bec568d7518b1504a602ed5376bb322e4dbb270"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:50:30.954589733+00:00"},"epss":{"cve":"CVE-2021-47321","score":0.00247,"percentile":0.1603,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}