{"cve":"CVE-2021-47461","nvd":{"published":"2024-05-22T07:15:11.040","modified":"2026-08-04T10:17:04.587","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nuserfaultfd: fix a race between writeprotect and exit_mmap()\n\nA race is possible when a process exits, its VMAs are removed by\nexit_mmap() and at the same time userfaultfd_writeprotect() is called.\n\nThe race was detected by KASAN on a development kernel, but it appears\nto be possible on vanilla kernels as well.\n\nUse mmget_not_zero() to prevent the race as done in other userfaultfd\noperations.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H","score":4.7},"cwes":["CWE-362"],"references":["https://git.kernel.org/stable/c/149958ecd0627a9f1e9c678c25c665400054cd6a","https://git.kernel.org/stable/c/3cda4bfffd4f755645577aaa9e96a606657b4525","https://git.kernel.org/stable/c/cb185d5f1ebf900f4ae3bf84cee212e6dd035aca","https://git.kernel.org/stable/c/149958ecd0627a9f1e9c678c25c665400054cd6a","https://git.kernel.org/stable/c/3cda4bfffd4f755645577aaa9e96a606657b4525"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:50:30.954589733+00:00"},"epss":{"cve":"CVE-2021-47461","score":0.00174,"percentile":0.06879,"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."]}