CVEs / CVE-2025-54309
CVE-2025-54309: CrushFTP Unprotected Alternate Channel Vulnerability
- Known exploited in the CISA KEV catalog since 22 Jul 2025
- critical 9.8 CVSS 3.1 (NVD)
- EPSS 93.4% chance of exploitation in the next 30 days, higher than 99% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
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.
Description
CrushFTP 10 before 10.8.5 and 11 before 11.3.4_23, when the DMZ proxy feature is not used, mishandles AS2 validation and consequently allows remote attackers to obtain admin access via HTTPS, as exploited in the wild in July 2025.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| CrushFTP CrushFTP | from 10, before 10.8.5 | 10.8.5 |
| CrushFTP CrushFTP | from 11, before 11.3.4_23 | 11.3.4_23 |
Exploitation
| In CISA KEV since | 22 Jul 2025 |
|---|---|
| Due date for US federal agencies | 12 Aug 2025 |
| Used in ransomware campaigns | Unknown |
| Required action | Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. |
Severity
| CVSS 3.1 | 9.8 criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HScored by NVD |
|---|---|
| Weakness | CWE-420 |
References
- CVE-2025-54309 on NVD
- CVE-2025-54309 in the CISA KEV catalog
- https://www.crushftp.com/crush11wiki/Wiki.jsp?page=CompromiseJuly2025 (cited by CISA)
- https://www.bleepingcomputer.com/news/security/crushftp-zero-day-exploited-in-attacks-to-gain-admin-access-on-servers/ Press/Media Coverage
- https://www.crushftp.com/crush11wiki/Wiki.jsp?page=CompromiseJuly2025 Vendor Advisory
- https://www.rapid7.com/blog/post/crushftp-zero-day-exploited-in-the-wild/ Press/Media Coverage
- https://www.vicarius.io/vsociety/posts/cve-2025-54309-detect-crushftp-vulnerability Third Party Advisory
- https://www.vicarius.io/vsociety/posts/cve-2025-54309-mitigate-crushftp-vulnerability Third Party Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-54309 US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.