CVE-2021-47461
userfaultfd: fix a race between writeprotect and exit_mmap()
HIGH 7.8
At a glance
- Source
- NVD
- EPSS
- EPSS 0.17 % · percentile 7 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- Linux
- NVD status
- Modified
Description
In the Linux kernel, the following vulnerability has been resolved: userfaultfd: fix a race between writeprotect and exit_mmap() A race is possible when a process exits, its VMAs are removed by exit_mmap() and at the same time userfaultfd_writeprotect() is called. The race was detected by KASAN on a development kernel, but it appears to be possible on vanilla kernels as well. Use mmget_not_zero() to prevent the race as done in other userfaultfd operations.
Weaknesses (CWE)
- CWE-362 — Race Condition
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | HIGH 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H | Linux |
| CVSS 3.1 | HIGH 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H | NVD · 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Secondary) |
| CVSS 3.1 | MEDIUM 4.7 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H | NVD · nvd@nist.gov (Primary) |
European references
- ENISA EUVD · EUVD-2021-34466
- GCVE · GCVE-0-2021-47461
CERT-FR advisories
- CERTFR-2026-AVI-1165 — Multiples vulnérabilités dans les produits IBM · cert.ssi.gouv.fr
- CERTFR-2025-AVI-0072 — Multiples vulnérabilités dans Juniper Secure Analytics · cert.ssi.gouv.fr
- CERTFR-2024-AVI-1032 — Multiples vulnérabilités dans le noyau Linux de Red Hat · cert.ssi.gouv.fr
- CERTFR-2024-AVI-0958 — Multiples vulnérabilités dans les produits IBM · cert.ssi.gouv.fr
- CERTFR-2024-AVI-0668 — Multiples vulnérabilités dans le noyau Linux de Red Hat · cert.ssi.gouv.fr
- CERTFR-2024-AVI-0526 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2024-AVI-0496 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 5.7 < 5.10.76cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 5.11 < 5.14.15cpe:2.3:o:linux:linux_kernel:5.15:rc1:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:5.15:rc2:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:5.15:rc3:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:5.15:rc4:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:5.15:rc5:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:5.15:rc6:*:*:*:*:*:*
Affected products
| Product | Versions |
|---|---|
| Linux · Linux | affected 63b2d4174c4ad1f40b48d7138e71bcb564c1fe03 < 3cda4bfffd4f755645577aaa9e96a606657b4525 ; affected 63b2d4174c4ad1f40b48d7138e71bcb564c1fe03 < 149958ecd0627a9f1e9c678c25c665400054cd6a ; affected 63b2d4174c4ad1f40b48d7138e71bcb564c1fe03 < cb185d5f1ebf900f4ae3bf84cee212e6dd035aca |
| Linux · Linux | affected 5.7 ; unaffected 0 < 5.7 ; unaffected 5.10.76 ≤ 5.10.* ; unaffected 5.14.15 ≤ 5.14.* ; unaffected 5.15 ≤ * |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |