CVE-2025-54309
Crushftp 10.0.0 – 10.8.5
Raw vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:HSummary
CVE-2025-54309 is a critical-severity Unprotected Alternate Channel (CWE-420) vulnerability in Crushftp Crushftp. Its CVSS base score is 9.0 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Fallback Channels (T1008); ranked in the top 0.2% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog.
The strongest mitigations our analysis identified map to SC-8 (Transmission Confidentiality and Integrity) and AC-4 (Information Flow Enforcement) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CrushFTP versions 10 prior to 10.8.5 and 11 prior to 11.3.4_23 are affected by CVE-2025-54309 when the DMZ proxy feature is disabled. The flaw stems from improper handling of AS2 validation, which permits unauthorized remote access over HTTPS and is tracked under CWE-420 with a CVSS 3.1 score of 9.0 reflecting high impact across confidentiality, integrity, and availability in a scoped context.
Remote attackers without authentication or user interaction can exploit the issue to obtain administrative privileges on the server. The vulnerability has already been leveraged in the wild during July 2025, enabling full administrative compromise of exposed CrushFTP instances that do not route traffic through the DMZ proxy.
Vendor guidance and third-party advisories direct administrators to upgrade immediately to the fixed releases and review the July 2025 compromise notice for indicators of prior access. The EPSS score reached a peak of 0.8284 with a current value of 0.7680, consistent with observed in-the-wild activity shortly after disclosure.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2025-21909
Vulnerability Data
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.
- CWE(s)
- KEV Date Added
- 22 July 2025
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Transmission confidentiality and integrity requirements apply to all transmitted data, preventing weaker protection on secondary channels.
Information flow enforcement requires consistent authorization and control over every path, directly stopping unequal protection of alternate channels.
Boundary protection mandates monitoring and control at all external and key internal interfaces, eliminating unprotected alternate channels.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Protecting all data-in-transit directly mitigates unequal channel protection though the control addresses broader transit scenarios.
Network protection from unauthorized access inherently requires securing every channel, not just primaries.
Network monitoring can surface use of unprotected alternate channels but does not prevent the design flaw.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Access restrictions may cover primary paths but leave alternate channels unprotected unless explicitly extended.
Secure authentication applies to primary channels but does not ensure alternate channels receive the same strength.
Network security controls ensure all channels receive equivalent protection, directly addressing unprotected alternate channels.
Security of network services requires consistent protection across all service channels, mitigating alternate-channel weaknesses.
Network segregation can reduce exposure of alternate channels but does not guarantee equivalent protection levels.
Cryptography can protect alternate channels but does not address the policy of applying equal protection across channels.