CVE-2025-31161 CrushFTP CrushFTP: login or permission bypass
In plain words: A door that should be locked is not: part of the system can be reached without a valid login or permission. The attacker gets in as a user or administrator without knowing a password.
Confirmed exploited by CISA on · US federal patch deadline Apr 28, 2025
What to do
- Install CrushFTP's security update for CrushFTP. If no update exists, follow the vendor's workaround or stop using the product until one ships.
- Keep a list of every internet-facing server you run so nothing is forgotten.
- Patch anything in this catalog first, ahead of normal patch cycles.
- Put admin and file-transfer apps behind a VPN or single sign-on instead of the open internet.
Who is affected
Work IT. Aimed mostly at company systems — you are affected through the companies you use, not your own phone.
What's at risk: Mass data theft and ransomware: a single flaw in a file-transfer or email server has exposed thousands of organisations at once.
The details
- Official name
- CrushFTP Authentication Bypass Vulnerability
- Product
- CrushFTP CrushFTP
- CISA description
- CrushFTP contains an authentication bypass vulnerability in the HTTP authorization header that allows a remote unauthenticated attacker to authenticate to any known or guessable user account (e.g., crushadmin), potentially leading to a full compromise.
- Type of flaw
- Login or permission bypass (CWE-305)
- Confirmed exploited
- Apr 7, 2025 — known to be used in ransomware attacks
- US federal patch deadline
- Apr 28, 2025
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Answering about CVE-2025-31161 ·
Questions about CVE-2025-31161
Is CVE-2025-31161 being exploited?
Yes. CISA added CVE-2025-31161 to its Known Exploited Vulnerabilities catalog on Apr 7, 2025, which means there is reliable evidence of real-world attacks, including by ransomware groups.
How do I fix CVE-2025-31161?
Install CrushFTP's security update for CrushFTP. If no update exists, follow the vendor's workaround or stop using the product until one ships. Keep a list of every internet-facing server you run so nothing is forgotten.
Am I affected by CVE-2025-31161?
Only if you use CrushFTP CrushFTP. Aimed mostly at company systems — you are affected through the companies you use, not your own phone.