Stored XSS via unvalidated CDN domain
Published Oct 25, 2025 · Updated Oct 25, 2025
Stored XSS in Fast Velocity Minify 3.5.1 and earlier allows remote authenticated users to inject scripts through the CDN domain setting. The fvm_save_settings function removes protocol prefixes from the saved CDN domain but accepts other non-hostname characters, while admin output renders saved settings without sufficient escaping. Exploitation requires administrator-level access and is limited to multisite installations or sites with unfiltered_html disabled; injected code runs when a user opens an affected page.
Summary
What happened
Stored XSS in Fast Velocity Minify 3.5.1 and earlier allows remote authenticated users to inject scripts through the CDN domain setting. The fvm_save_settings function removes protocol prefixes from the saved CDN domain but accepts other non-hostname characters, while admin output renders saved settings without sufficient escaping. Exploitation requires administrator-level access and is limited to multisite installations or sites with unfiltered_html disabled; injected code runs when a user opens an affected page.
The record
- CVE
- CVE-2025-12034
- Published
- Oct 25, 2025
- Updated
- Oct 25, 2025
- Vendor
- Raul Peixoto
- Product
- Fast Velocity Minify
- Classifications
- CWE-79, T1059.007
- Attack vector
- network
- Privileges
- admin
Timeline
How it unfolded
- Oct 25, 2025CVE publishedPublication date reported by the CVE source.
- Oct 25, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=* <=3.5.1
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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