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Threats / CrushFTP / CVE-2025-31161
CVE-2025-31161 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

CrushFTP vulnerability

CrushFTP contains an authentication bypass vulnerability in HTTP authorization headers allowing remote unauthenticated attackers to authenticate as any known user account, potentially enabling full system compromise.

Verdict

Today item, not a backlog item.

Remote unauthenticated attackers can bypass authentication mechanisms in CrushFTP by manipulating HTTP authorization headers, gaining unauthorized access to user accounts including administrative accounts without valid credentials.

CISA KEV Yes · 2025-04-073Ransomware use Flagged3EPSS 0.99957 (verify live)4Exploit Weaponized · public PoC5
01

Is it exploitable?

— the evidence, ranked above the score
Exploit available
Fully weaponized — public exploit code is cataloged for this vulnerability.We link the existence of the exploit; we do not host or redistribute payloads.
Reported exploitation
41 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2025-04-07), flagged for known ransomware use.
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.99957 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: CrushFTP, CrushFTP. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-305 CWE-305.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
02

Who’s exploiting it?

— attribution turns risk into urgency
Attribution not established

No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.

03

Why it matters

— the attack path, told twice: adversary, then board
1

Front door — unauthenticated access narrative 1

Attacker
I craft HTTP requests with manipulated authorization headers to bypass authentication checks.
Business
Attackers gain unauthorized administrative access to CrushFTP servers without requiring valid credentials.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I authenticate as the crushadmin account or other known users by exploiting the header validation flaw.
Business
Full control of file transfer infrastructure and stored data becomes accessible to threat actors.
3

Lateral reach — past segmentation narrative 3

Attacker
I establish persistent access and exfiltrate sensitive files or deploy ransomware payloads across the system.
Business
Organizations face data theft, operational disruption, and extortion demands from ransomware deployment.
04

What to do

— defensible action
  • Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05

Coverage & confidence

— what we know, and what we don’t

Established (cited)

  • KEV listing (CISA)
  • Ransomware-use flag (CISA)
  • EPSS probability (FIRST)
  • Weaponized exploit available (VulnCheck)
  • 41 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Public exploit availability
  • Catalogued by mitre (CNA)
  • Named finder/reporter credit (CVE.org)
  • Coverage gaps — stated, not hidden

  • No EUVD / GCVE mirror in feed — single-authority dependency for the identifier.
  • EPSS & exposure are time-varying; verify live at the source.
  • Threat-actor attribution not established from feed data — absence of a name is not absence of compromise.
  • Disclosure & credit2