Service interruption via rtrim regex backtracking
Published Nov 2, 2021 · Updated Aug 3, 2024
Regular expression denial of service in validator.js before 13.7.0 allows attackers to cause a service interrupt through rtrim or trim. The default rtrim path applies the nested quantified pattern /(\s)+$/ to input, and trim reaches the same code after left trimming. A consuming application must pass attacker-controlled strings to either sanitizer; a long whitespace suffix followed by a nonmatching character can consume excessive CPU without altering data.
Summary
What happened
Regular expression denial of service in validator.js before 13.7.0 allows attackers to cause a service interrupt through rtrim or trim. The default rtrim path applies the nested quantified pattern /(\s)+$/ to input, and trim reaches the same code after left trimming. A consuming application must pass attacker-controlled strings to either sanitizer; a long whitespace suffix followed by a nonmatching character can consume excessive CPU without altering data.
The record
- CVE
- CVE-2021-3765
- Published
- Nov 2, 2021
- Updated
- Aug 3, 2024
- Vendor
- validatorjs
- Product
- validator.js
- Classifications
- CWE-1333, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Nov 2, 2021CVE publishedPublication date reported by the CVE source.
- Aug 3, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=unspecified <13.7.0
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- Huntr denial-of-service exploit referenceproof of concept · unverified
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Technologies
Your stack
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Your stack
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