Phishing and script execution via unsanitized posts
Published Jul 17, 2025 · Updated Jul 17, 2025
HTML injection in Fedify Hollo before 0.6.5 allows remote attackers to submit forms or run scripts through federated posts. The federated-post renderer passes received HTML containing form, script, and other dangerous elements to clients without strict allowlist sanitization. A user must view or interact with the malicious content, enabling phishing, unintended requests, or script execution in the client's origin.
Summary
What happened
HTML injection in Fedify Hollo before 0.6.5 allows remote attackers to submit forms or run scripts through federated posts. The federated-post renderer passes received HTML containing form, script, and other dangerous elements to clients without strict allowlist sanitization. A user must view or interact with the malicious content, enabling phishing, unintended requests, or script execution in the client's origin.
The record
- CVE
- CVE-2025-53941
- Published
- Jul 17, 2025
- Updated
- Jul 17, 2025
- Vendor
- Fedify
- Product
- Hollo
- Classifications
- CWE-79, T1056.003
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 17, 2025CVE publishedPublication date reported by the CVE source.
- Jul 17, 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=< 0.6.5
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- Embedded federated-form submission proof of conceptproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
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Your stack
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