CVE-2021-3864
kernel
HIGH 7.0
En bref
- Source
- NVD
- EPSS
- EPSS 0.78 % · centile 56 ()
- État
- PUBLISHED
- Publiée
- Mise à jour
- Attribuée par
- redhat
- Statut NVD
- Modified
Description
A flaw was found in the way the dumpable flag setting was handled when certain SUID binaries executed its descendants. The prerequisite is a SUID binary that sets real UID equal to effective UID, and real GID equal to effective GID. The descendant will then have a dumpable value set to 1. As a result, if the descendant process crashes and core_pattern is set to a relative value, its core dump is stored in the current directory with uid:gid permissions. An unprivileged local user with eligible root SUID binary could use this flaw to place core dumps into root-owned directories, potentially resulting in escalation of privileges.
Faiblesses (CWE)
- CWE-284 — Contrôle d'accès incorrect
Références
- https://www.openwall.com/lists/oss-security/2021/10/20/2
- https://bugzilla.redhat.com/show_bug.cgi?id=2015046
- https://access.redhat.com/security/cve/CVE-2021-3864
- https://lore.kernel.org/all/20211221021744.864115-1-longman%40redhat.com/
- https://lore.kernel.org/lkml/20211228170910.623156-1-wander%40redhat.com/
- https://lore.kernel.org/all/20211226150310.GA992%401wt.eu/
- https://security-tracker.debian.org/tracker/CVE-2021-3864
Scores
| Version | Score | Vecteur | Évalué par |
|---|---|---|---|
| CVSS 3.1 | HIGH 7.0 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H | NVD · nvd@nist.gov (Primary) |
Références européennes
- ENISA EUVD · EUVD-2021-27099
- GCVE · GCVE-0-2021-3864
Avis du CERT-FR
- CERTFR-2026-AVI-0326 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0316 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
Configurations affectées (CPE NVD)
cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:*cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:*cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*
Produits affectés
| Produit | Versions |
|---|---|
| kernel | affected Not Known |
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 |