CVE-2022-24713
Vulnérabilité élevée dans regex (rust-lang)
Description
regex is an implementation of regular expressions for the Rust language. The regex crate features built-in mitigations to prevent denial of service attacks caused by untrusted regexes, or untrusted input matched by trusted regexes. Those (tunable) mitigations already provide sane defaults to prevent attacks. This guarantee is documented and it's considered part of the crate's API. Unfortunately a bug was discovered in the mitigations designed to prevent untrusted regexes to take an arbitrary amount of time during parsing, and it's possible to craft regexes that bypass such mitigations. This makes it possible to perform denial of service attacks by sending specially crafted regexes to services accepting user-controlled, untrusted regexes. All versions of the regex crate before or equal to 1.5.4 are affected by this issue. The fix is include starting from regex 1.5.5. All users accepting user-controlled regexes are recommended to upgrade immediately to the latest version of the regex crate. Unfortunately there is no fixed set of problematic regexes, as there are practically infinite regexes that could be crafted to exploit this vulnerability. Because of this, it us not recommend to deny known problematic regexes.
Gravité et risque d'exploitation
CVE-2022-24713 obtient un score CVSS de 7.5/10, soit une gravité élevée. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 14.46 %, ce qui la place devant 96.6 % des CVE référencées.
Que faire ?
- Vérifiez si regex (versions < 1.5.5) est présent sur votre parc.
- Appliquez le correctif ou la version corrigée indiqués dans les références de l'éditeur.
- À défaut de correctif, limitez l'exposition (filtrage réseau, désactivation du composant).
- Automatisez la détection : les agents CVE Heimdall (gratuits, open source) corrèlent l'inventaire de vos serveurs avec la base CVE.
Références
- https://github.com/rust-lang/regex/security/advisories/GHSA-m5pq-gvj9-9vr8
- https://github.com/rust-lang/regex/commit/ae70b41d4f46641dbc45c7a4f87954aea356283e
- https://groups.google.com/g/rustlang-security-announcements/c/NcNNL1Jq7Yw
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PDOWTHNVGBOP2HN27PUFIGRYNSNDTYRJ/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JANLZ3JXWJR7FSHE57K66UIZUIJZI67T/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/O3YB7CURSG64CIPCDPNMGPE4UU24AB6H/
- https://lists.debian.org/debian-lts-announce/2022/04/msg00003.html
- https://www.debian.org/security/2022/dsa-5113
- https://lists.debian.org/debian-lts-announce/2022/04/msg00009.html
- https://www.debian.org/security/2022/dsa-5118
- https://security.gentoo.org/glsa/202208-08
- https://security.gentoo.org/glsa/202208-14