Service interruption via reCustomIgnore catastrophic backtracking
Published Oct 31, 2022 · Updated Jun 1, 2025
Regular expression denial of service in kangax html-minifier 4.0.0 allows remote attackers to interrupt service via crafted HTML input. The minify function joins ignoreCustomFragments patterns beneath a repeated group to build reCustomIgnore, then applies that expression to the entire value, enabling catastrophic backtracking on long nonmatching text. An application must pass attacker-controlled content to minify; successful exploitation monopolizes the Node.js process rather than altering or exposing data.
Summary
What happened
Regular expression denial of service in kangax html-minifier 4.0.0 allows remote attackers to interrupt service via crafted HTML input. The minify function joins ignoreCustomFragments patterns beneath a repeated group to build reCustomIgnore, then applies that expression to the entire value, enabling catastrophic backtracking on long nonmatching text. An application must pass attacker-controlled content to minify; successful exploitation monopolizes the Node.js process rather than altering or exposing data.
The record
- CVE
- CVE-2022-37620
- Published
- Oct 31, 2022
- Updated
- Jun 1, 2025
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-400, CWE-1333, T1499
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Oct 31, 2022CVE publishedPublication date reported by the CVE source.
- Jun 1, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What is affected?
Affected products and versions are unavailable in this record.
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
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
- Snyk html-minifier ReDoS proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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