// For flags

CVE-2022-24713

Regular expression denial of service in Rust's regex crate

Severity Score

7.5
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

1
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

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.

regex es una implementación de expresiones regulares para el lenguaje Rust. La caja de regex presenta mitigaciones incorporadas para prevenir ataques de denegación de servicio causados por regexes no confiables, o por entradas no confiables coincidentes con regexes confiables. Estas mitigaciones (sintonizables) ya proporcionan valores predeterminados sanos para prevenir ataques. Esta garantía está documentada y se considera parte de la API de la caja. Desafortunadamente, se descubrió un error en las mitigaciones diseñadas para evitar que las expresiones regulares no confiables tomen una cantidad arbitraria de tiempo durante el análisis, y es posible crear expresiones regulares que eludan dichas mitigaciones. Esto hace posible realizar ataques de denegación de servicio enviando regexes especialmente diseñados a servicios que aceptan regexes no confiables controlados por el usuario. Todas las versiones de regex crate anteriores o iguales a la 1.5.4 están afectadas por este problema. La corrección se incluye a partir de regex 1.5.5. Se recomienda a todos los usuarios que acepten regexes controlados por el usuario que actualicen inmediatamente a la última versión del regex crate. Lamentablemente, no existe un conjunto fijo de regexes problemáticos, ya que hay prácticamente infinitas regexes que podrían ser creadas para explotar esta vulnerabilidad. Por ello, no recomendamos negar las regex problemáticas conocidas

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Attack Vector
Network
Attack Complexity
Low
Authentication
None
Confidentiality
None
Integrity
None
Availability
Partial
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2022-02-10 CVE Reserved
  • 2022-03-08 CVE Published
  • 2022-06-05 First Exploit
  • 2024-08-03 CVE Updated
  • 2024-11-21 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
CWE
  • CWE-400: Uncontrolled Resource Consumption
  • CWE-1333: Inefficient Regular Expression Complexity
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Rust-lang
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Regex
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< 1.5.5
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rust
Affected
Fedoraproject
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Fedora
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34
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-
Affected
Fedoraproject
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Fedora
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35
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-
Affected
Fedoraproject
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Fedora
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36
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-
Affected
Debian
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Debian Linux
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9.0
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-
Affected
Debian
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Debian Linux
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10.0
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-
Affected
Debian
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Debian Linux
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11.0
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-
Affected