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Full vulnerability report · 2025
CVE-2025-54309High confidence

CrushFTP Unprotected Alternate Channel Vulnerability

CrushFTP · CrushFTP

9.0CriticalCVSS 3.1
Recommended action
Mitigate now

CISA confirms exploitation in the wild and lists 2025-08-12 as the remediation due date.

Mitigation available
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityCriticalOperational priority:Critical, unchanged from published severity.unchanged

Evidence used

  • CISA confirms exploitation in the wild.
  • The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
  • EPSS is 94.91% for the current model date.

Compensating controls

  • Apply the linked authoritative mitigation while planning the permanent fix.
  • Restrict the affected network interface to trusted sources where business-safe.
  • Increase monitoring for the attack path and post-exploitation behaviour described in the report.

Verification

  1. Confirm that the asset runs CrushFTP CrushFTP and falls inside the recorded affected range.
  2. Recheck the vendor advisory before scheduling a change because no verified fixed version is currently retained.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: Within 3 daysRemediation target: Within 90 days

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2025-21909

CISA KEV mirrored by ENISA

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.

EUVD state
Present in the current official mapping
Known exploitation
Recorded by ENISA since 22 Jul 2025. Evidence sources: cisa_kev.
ENISA score
9.0 · CVSS 3.1
Advisory evidence
2 linked advisory records
Explicit mitigation evidence

Only statements that explicitly mention a fix, patch, update, workaround or mitigation are shown here.

  • csaf_ncscnl · NCSC-2025-0234Kwetsbaarheid verholpen in CrushFTP
Recommended actionMitigate now

CISA confirms exploitation in the wild and lists 2025-08-12 as the remediation due date.

Mitigation available
01

What, why and how

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.

What

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.

Why

The product protects a primary channel, but it does not use the same level of protection for an alternate channel.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

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.

Why

The product protects a primary channel, but it does not use the same level of protection for an alternate channel.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
Confirmed in the wild

CISA added this CVE to its Known Exploited Vulnerabilities catalogue on 2025-07-22.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
a network path → Unprotected Alternate Channel → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
None
Attack complexity
High: exploitation depends on specific conditions
Security boundary
Changed: exploitation can affect a different security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-420 ↗

CWE-420: Unprotected Alternate Channel. The product protects a primary channel, but it does not use the same level of protection for an alternate channel.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACHighAttack complexity: Successful exploitation depends on specific conditions outside the attacker's direct control.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SChangedScope: The attack can affect a component governed by a different security authority.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major loss.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
NetworkUnauthenticatedCWE-420CISA KEV
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

ENISA EUVD · EUVD-2025-21909Known-exploited evidence recorded

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.

Official EUVD record ↗
BSI · German · WID-SEC-2025-1608CrushFTP: Schwachstelle ermöglicht Erlangen von Administratorrechten

Ein entfernter, anonymer Angreifer kann eine Schwachstelle in CrushFTP ausnutzen, um Administratorrechte zu erlangen.

Official advisory ↗
Canadian Centre for Cyber Security · English · AV25-432CrushFTP security advisory (AV25-432)

On July 18, 2025, CrushFTP published a security advisory to address a vulnerability in the following product: CrushFTP is aware that an exploit for CVE-2025-54309 exists in the wild.

Official advisory ↗
Cyber Security Agency of Singapore · English · CSA-SB-20250724Security Bulletin 24 Jul 2025 [701KB]

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 24 Jul 2025 [701KB], published on 24 July 2025. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2025-009745CrushFTP における保護されていない代替チャネルに関する脆弱性

CrushFTP には、保護されていない代替チャネルに関する脆弱性が存在します。

Official advisory ↗
KISA KrCERT/CC · Korean · KNVD-6539CrushFTP 제품 보안 업데이트 권고

CrushFTP에서 발생하는 원격 권한 상승 취약점(CVE-2025-54309) [1][2]

Official advisory ↗
KISA KrCERT/CC · Korean · KNVD-6540美 CISA 발표 주요 Exploit 정보공유(Update. 2025-07-22)

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.

Official advisory ↗
NCSC-NL · Dutch · NCSC-2025-0234Kwetsbaarheid verholpen in CrushFTP

De kwetsbaarheid bevindt zich in de AS2-validatie van CrushFTP. Deze kwetsbaarheid stelt een aanvaller in staat om via HTTPS administratieve toegang te verkrijgen, vooral wanneer de DMZ-proxyfunctie niet wordt gebruikt. De kwetsbaarheid is actief misbruikt, met meldingen die in juli 2025 zijn verschenen. Ongeautoriseerde toegang kan leiden tot verdere exploitatie van de getroffen systemen. Diverse onderzoekers publiceren inmiddels Proof-of-Concept-code (PoC) waarmee de kwetsbaarheid kan worden aangetoond. Daadwerkelijk misbruik is op dit moment nog niet eenvoudig te realiseren, omdat een zgn. 'Race condition' moet worden gerealiseerd. Het NCSC acht het waarschijnlijk dat op korte termijn werkende exploitcode wordt gepubliceerd, waarmee grootschalig misbruik eenvoudiger wordt.

Official advisory ↗
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Mitigation available
Affected
CrushFTP: 10 < 10.8.5, 11 < 11.3.4_23
Fixed
No fixed version is explicitly recorded in the structured CVE data.
Action
The Cyber Centre encourages users and administrators to review the provided web link, follow the recommended mitigation and apply the necessary updates.
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04

Evidence and provenance

Published 18 Jul 2025 · Last source change 21 Oct 2025, 22:45 UTC · CWE-420 · Unprotected Alternate Channel

CVE recordCVE.org · 5.1
CVSS sourceCNA
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2025-21909
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD enriched

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates ↗
  1. Vendor guidanceAuthoritative vendor guidance changed: removed remediation: cyber.gc.ca/crushftp-security-advisory-av25-432.
    Before
    remediation: cyber.gc.ca/crushftp-security-advisory-av25-432 · vendor advisory: crushftp.com/Wiki.jsp?page=CompromiseJuly2025
    After
    vendor advisory: crushftp.com/Wiki.jsp?page=CompromiseJuly2025
    cve@mitre.org ↗
  2. Remediation statusRemediation status changed from Mitigation available to Awaiting fix.
    Before
    Mitigation available
    After
    Awaiting fix
    cve@mitre.org ↗
  3. Affected versionsThe structured affected or fixed version information changed.
    Before
    10 < 10.8.5; 11 < 11.3.4_23 · Fixed: No fixed version is explicitly recorded in the structured CVE data.
    After
    CrushFTP: 10 < 10.8.5, 11 < 11.3.4_23 · Fixed: No fixed version is explicitly recorded in the structured CVE data.
    CNA ↗
  4. Remediation statusRemediation status changed from Awaiting fix to Mitigation available.
    Before
    Awaiting fix
    After
    Mitigation available
    Canadian Centre for Cyber Security ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Added to CISA KEV
Remediation guidance recorded
ENISA EUVD · EUVD-2025-21909↗Canadian Centre for Cyber Security remediation guidance↗CISA KEV record↗CVE authority or vendor reference↗Official CVE record (CNA and ADP data)↗NVD record↗
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2025-54309 · cve.blacktree.nl