CVE-2025-15104 (GCVE-0-2025-15104)
Vulnerability from cvelistv5 – Published: 2026-01-16 14:00 – Updated: 2026-01-16 14:30
VLAI
EPSS
VEX
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).
Severity
SSVC
Exploitation: poc
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-01-16 14:30 UTC
CWE
- CWE-918 - Server-Side Request Forgery (SSRF)
Assigner
Fluid Attacks
CNA
References
2 references
| URL | Tags |
|---|---|
| https://fluidattacks.com/advisories/europe | third-party-advisory |
| https://github.com/validator/validator | product |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| The Nu Html Checker | The Nu Html Checker |
Affected:
latest - commit:23f090a11bab8d0d4e698f1ffc197a4fe226a9cd
cpe:2.3:a:the_nu_html_checker:the_nu_html_checker:latest_-_commit_23f090a11bab8d0d4e698f1ffc197a4fe226a9cd:*:windows:*:*:*:*:* cpe:2.3:a:the_nu_html_checker:the_nu_html_checker:latest_-_commit_23f090a11bab8d0d4e698f1ffc197a4fe226a9cd:*:linux:*:*:*:*:* cpe:2.3:a:the_nu_html_checker:the_nu_html_checker:latest_-_commit_23f090a11bab8d0d4e698f1ffc197a4fe226a9cd:*:macos:*:*:*:*:* |
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| Author | Source | Type | Date | Other |
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Nomenclature
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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