What’s Vulnerable › Vulnerabilities

CVE-2021-23382: Regular Expression Denial of Service (ReDoS)

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 2.6% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2021-04-26 · updated 2026-06-17
• Weakness: CWE-1333

Description

The package postcss before 8.2.13 are vulnerable to Regular Expression Denial of Service (ReDoS) via getAnnotationURL() and loadAnnotation() in lib/previous-map.js. The vulnerable regexes are caused mainly by the sub-pattern \/\*\s* sourceMappingURL=(.*).

Affected products

• postcss: before 7.0.36; from 8.0.0 before 8.2.13 — fixed in 7.0.36, 8.2.13
• Npm Postcss: from 8.0.0 before 8.2.13; before 7.0.36 — fixed in 8.2.13, 7.0.36

How to fix

Upgrade to a fixed version: postcss 7.0.36, 8.2.13; Npm Postcss 8.2.13, 7.0.36. Check the vendor advisory for mitigations.

References

• https://github.com/postcss/postcss/commit/2b1d04c867995e55124e0a165b7c6622c1735956
• https://snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-1255641
• https://snyk.io/vuln/SNYK-JS-POSTCSS-1255640
• https://github.com/postcss/postcss/commit/2b1d04c867995e55124e0a165b7c6622c1735956
• https://snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-1255641
• https://snyk.io/vuln/SNYK-JS-POSTCSS-1255640

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