What’s Vulnerable › Vulnerabilities

CVE-2021-23388: Regular Expression Denial of Service (ReDoS)

• Severity: medium (CVSS 5.3 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.7% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-06-01 · updated 2026-06-17

Description

The package forms before 1.2.1, from 1.3.0 and before 1.3.2 are vulnerable to Regular Expression Denial of Service (ReDoS) via email validation.

Affected products

• HackerOne forms node module: before 1.2.1; from 1.3.0 before 1.3.2 — fixed in 1.2.1, 1.3.2

How to fix

Upgrade to a fixed version: HackerOne forms node module 1.2.1, 1.3.2. Check the vendor advisory for mitigations.

References

• https://github.com/caolan/forms/pull/214
• https://github.com/caolan/forms/pull/214/commits/d4bd5b5febfe49c1f585f162e04ec810f8dc47a0
• https://snyk.io/vuln/SNYK-JS-FORMS-1296389
• https://github.com/caolan/forms/pull/214
• https://github.com/caolan/forms/pull/214/commits/d4bd5b5febfe49c1f585f162e04ec810f8dc47a0
• https://snyk.io/vuln/SNYK-JS-FORMS-1296389

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