7.5 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
5 Medium
CVSS2
Access Vector
NETWORK
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:N/I:N/A:P
0.004 Low
EPSS
Percentile
71.9%
> This is a cross-post of the official security advisory. The official advisory contains a signed version with our PGP key, as well.
The Rust Security Response WG was notified that the regex
crate did not properly limit the complexity of the regular expressions (regex) it parses. An attacker could use this security issue to perform a denial of service, by sending a specially crafted regex to a service accepting untrusted regexes. No known vulnerability is present when parsing untrusted input with trusted regexes.
This issue has been assigned CVE-2022-24713. The severity of this vulnerability is “high” when the regex
crate is used to parse untrusted regexes. Other uses of the regex
crate are not affected by this vulnerability.
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.
We recommend everyone accepting user-controlled regexes 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, we do not recommend denying known problematic regexes.
We want to thank Addison Crump for responsibly disclosing this to us according to the Rust security policy, and for helping review the fix.
We also want to thank Andrew Gallant for developing the fix, and Pietro Albini for coordinating the disclosure and writing this advisory.
github.com/rust-lang/regex
github.com/rust-lang/regex/commit/ae70b41d4f46641dbc45c7a4f87954aea356283e
github.com/rust-lang/regex/security/advisories/GHSA-m5pq-gvj9-9vr8
groups.google.com/g/rustlang-security-announcements/c/NcNNL1Jq7Yw
lists.debian.org/debian-lts-announce/2022/04/msg00003.html
lists.debian.org/debian-lts-announce/2022/04/msg00009.html
lists.fedoraproject.org/archives/list/[email protected]/message/JANLZ3JXWJR7FSHE57K66UIZUIJZI67T
lists.fedoraproject.org/archives/list/[email protected]/message/O3YB7CURSG64CIPCDPNMGPE4UU24AB6H
lists.fedoraproject.org/archives/list/[email protected]/message/PDOWTHNVGBOP2HN27PUFIGRYNSNDTYRJ
nvd.nist.gov/vuln/detail/CVE-2022-24713
rustsec.org/advisories/RUSTSEC-2022-0013.html
security.gentoo.org/glsa/202208-08
security.gentoo.org/glsa/202208-14
www.debian.org/security/2022/dsa-5113
www.debian.org/security/2022/dsa-5118
7.5 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
5 Medium
CVSS2
Access Vector
NETWORK
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:N/I:N/A:P
0.004 Low
EPSS
Percentile
71.9%