GitHub Advisoryadvisory · Maven, npm

GHSA-fccg-7w3p-w66f Nu Html Checker (vnu) contains a Server-Side Request Forgery (SSRF) vulnerability

MEDIUM Published 2026-01-16 Modified 2026-01-16 Official page ↗
Aliases
CVE-2025-15104
Ecosystem
Maven, npm
Packages
nu.validator:validator, vnu-jar
Severity
Moderate
CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:N/SA:N/E:P
Weaknesses
CWE-918
Reviewed
2026-01-16

Affected packages

• Maven nu.validator:validator: <= 26.1.11 (no fix yet) • npm vnu-jar: <= 26.1.11 (no fix yet)

Description

Nu Html Checker (validator.nu) contains a restriction bypass that allows remote attackers to make the server perform arbitrary HTTP/HTTPS requests to internal resources, including localhost services. While the validator implements hostname-based protections to block direct access to localhost and 127.0.0.1, these controls can be bypassed using DNS rebinding techniques or domains that resolve to loopback addresses.This issue affects The Nu Html Checker (vnu): latest (commit 23f090a11bab8d0d4e698f1ffc197a4fe226a9cd).

Related

Alias · CVE (1)

  • CVE-2025-15104 Nu Html Checker (validator.nu) contains a restriction bypass that allows remote attackers to make the server perform arbitrary HTTP/HTTPS… vulnerability

Weakness · CWE (1)

  • CWE-918 Server-Side Request Forgery weakness

References