NIST deprecates RSA-2048 from 2030. Find every one of them before attackers do.
📦
📦 npm
Not in CISA KEV
MEDIUM severity

CVE-2025-56200 — validator

MEDIUMFix: validatorjs/validator.js#2608

CVE-2025-56200 is a medium-severity (CVSS 6.1) Cross-site Scripting (XSS) vulnerability in validator. A fix is available for validator — see the affected versions and patch details below.

validator.js has a URL validation bypass vulnerability in its isURL function

Also known asGHSA-9965-vmph-33xx
Published
Updated
Affected
1 pkg
Patched
1 / 1
Exploits
None indexed
Exploitation data as of Nov 1, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

  • CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2025-56200.

EPSS Exploitation Probability

via FIRST.org ↗
0.3%probability of exploitation in next 30 days
Lower Risk0.00%
Lower risk than most CVEs26th percentile — riskier than 26% of all scored CVEsHighest risk
0.00%0.27%0.55%0.82%0.1%0.3%May 26Aug 26Nov 26

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

1 pkg affected

How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.

7Kother npm packages depend on this — each one inherits the vulnerability until it's patched upstream
validatornpm
35.7Mdownloads / week

Description

A URL validation bypass vulnerability exists in validator.js prior to version 13.15.20. The isURL() function uses '://' as a delimiter to parse protocols, while browsers use ':' as the delimiter. This parsing difference allows attackers to bypass protocol and domain validation by crafting URLs leading to XSS and Open Redirect attacks.

Affected Packages

1 total 1 fixed
EcosystemPackageVulnerable rangeFix
📦npmvalidatorall versions13.15.20npm install validator@13.15.20

Affected Products

1 product · 1 configurations
Application
validatorvalidator_project
≤ 3.15.15
range

Detection & mitigation playbook

Open-source dependency

  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for validator, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

  2. Fix

    Update validator to 13.15.20 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-56200 is resolved across your whole dependency graph.

  3. Workarounds

    Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

Frequently Asked Questions

A URL validation bypass vulnerability exists in validator.js prior to version 13.15.20. The isURL() function uses '://' as a delimiter to parse protocols, while browsers use ':' as the delimiter. This parsing difference allows attackers to bypass protocol and domain validation by crafting URLs leading to XSS and Open Redirect attacks.
O3 Security · Impact-Aware SCA

Is CVE-2025-56200 in your dependencies?

Find it across npm, including transitive dependencies.

Scan my dependencies How O3 SCA works
CVE-2025-56200: validator XSS — Fixed in 13.15.20