CrushFTP flaws being used in attacks

CISA lists 3 flaws in CrushFTP products as being used in attacks, most recently on 22 Jul 2025. 1 has been used in ransomware.

What to do

1. Update every CrushFTP product you use.Install the updates CrushFTP offers, on every device, and restart when asked. Each flaw below has a fix or clear advice; that’s one of CISA’s conditions for listing it.
2. If someone looks after IT for you, send them this page.Many of these are in equipment you don’t see: routers, firewalls, servers, the office network. Ask them to confirm each one is fixed, or that you don’t use the product.
3. Check anything else in the lookup.Search any app, company or CVE. Not being on CISA’s list doesn’t mean safe: keep updating either way.

Every flaw, newest first

1. Being used in attacksAdded by CISA on 22 Jul 2025
   CrushFTP
   CVE-2025-54309CrushFTP Unprotected Alternate Channel Vulnerability
   CrushFTP contains an unprotected alternate channel vulnerability. When the DMZ proxy feature is not used, mishandles AS2 validation and consequently allows remote attackers to obtain admin access via HTTPS.
   CISA’s required actionApply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
   CVE recordNVD
2. Being used in attacksUsed in ransomwareAdded by CISA on 7 Apr 2025
   CrushFTP
   CVE-2025-31161CrushFTP Authentication Bypass Vulnerability
   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.
   CISA’s required actionApply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
   CVE recordNVD
3. Being used in attacksAdded by CISA on 24 Apr 2024
   CrushFTP
   CVE-2024-4040CrushFTP VFS Sandbox Escape Vulnerability
   CrushFTP contains an unspecified sandbox escape vulnerability that allows a remote attacker to escape the CrushFTP virtual file system (VFS).
   CISA’s required actionApply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
   CVE recordNVD

From CISA’s Known Exploited Vulnerabilities catalog, updated 21 Oct 2026 (version 2026.10.21). CISA’s required actions are written for US government agencies. CrushFTP on CISA’s site.