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Vulnerability record · CVE-2021-3765 · published 2 November 2021
CVE-2021-3765: Validator project validator inefficient regular expression (redos) vulnerability
Validator Project · Validator
validator.js is vulnerable to Inefficient Regular Expression Complexity
7.5 CVSS 3.1 High EPSS 1.8% · top 22.7% CWE-1333 · Inefficient regular expression (ReDoS)
7.5CVSS 3.1 base score, v2 5.0
1.8%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
4References, 2 tagged exploit
17 Jun 2026Last modified by NVD
Description
validator.js is vulnerable to Inefficient Regular Expression Complexity
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
| Link | Tags |
|---|---|
| https://github.com/validatorjs/validator.js/commit/496fc8b2a7f5997acaaec33cc44d0b8dba5fb5e1 | PatchThird Party Advisory |
| https://huntr.dev/bounties/c37e975c-21a3-4c5f-9b57-04d63b28cfc9 | ExploitIssue TrackingPatchThird Party Advisory |
| https://github.com/validatorjs/validator.js/commit/496fc8b2a7f5997acaaec33cc44d0b8dba5fb5e1 | PatchThird Party Advisory |
| https://huntr.dev/bounties/c37e975c-21a3-4c5f-9b57-04d63b28cfc9 | ExploitIssue TrackingPatchThird Party Advisory |
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Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
7.7CVE-2025-12758Validator project validator vulnerabilityVersions of the package validator before 13.15.22 are vulnerable to Incomplete Filtering of One or More Instances of Special Elements in the isLength…EPSS 0.52%6.1CVE-2025-56200Validator project validator cross-site scripting vulnerabilityA URL validation bypass vulnerability exists in validator.js through version 13.15.15. The isURL() function uses '://' as a delimiter to parse protoc…EPSS 0.32%
Source: NIST National Vulnerability Database (record CVE-2021-3765), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.
