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1 vulnerability by The Nu Html Checker

CVE-2025-15104 (GCVE-0-2025-15104)

Vulnerability from cvelistv5 – Published: 2026-01-16 14:00 – Updated: 2026-01-16 14:30
VLAI?
Title
Nu Html Checker (validator.nu) - Restriction bypass vulnerability allowing local SSRF
Summary
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).
CWE
  • CWE-918 - Server-Side Request Forgery (SSRF)
Assigner
Impacted products
Vendor Product Version
The Nu Html Checker The Nu Html Checker Affected: latest - commit:23f090a11bab8d0d4e698f1ffc197a4fe226a9cd
Create a notification for this product.
Credits
Oscar Uribe
Show details on NVD website

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