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Threats / FatPipe / CVE-2021-27860
CVE-2021-27860 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

FatPipe WARP, IPVPN, and MPVPN software vulnerability

FatPipe WARP, IPVPN, and MPVPN web management interfaces allow unauthenticated remote file upload to arbitrary filesystem locations, enabling code execution and system compromise.

Verdict

Today item — known-exploited.

A critical unauthenticated file upload vulnerability in FatPipe network appliance management interfaces permits arbitrary file placement on affected systems. Exploitation requires network access to the web interface and enables remote code execution.

CISA KEV Yes · 2022-01-103EPSS 0.39824 (verify live)4
01

Is it exploitable?

— the evidence, ranked above the score
Reported exploitation
7 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 2022-01-10).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.39824 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: FatPipe, WARP, IPVPN, and MPVPN software. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-434 Unrestricted File Upload — weakness family: Path traversal / file.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
WeaknessCWE-434 · Unrestricted File UploadPath traversal / file
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 identify the FatPipe management interface exposed on the network and confirm it accepts unauthenticated file uploads.
Business
Network perimeter security fails to prevent unauthorized access to critical appliance management functions.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I upload a malicious file to a web-accessible directory or system path that will be executed by the application.
Business
Arbitrary code execution on network infrastructure appliances compromises all traffic and data passing through them.
3

Lateral reach — past segmentation narrative 3

Attacker
I gain shell access or administrative control over the compromised FatPipe device and pivot to connected networks.
Business
VPN and MPVPN infrastructure becomes a beachhead for lateral movement across enterprise networks and data exfiltration.
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)
  • EPSS probability (FIRST)
  • 7 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Catalogued by certcc (CNA)
  • 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.
  • No finder/reporter credit recorded in the public CVE entry — the work behind this find is unattributed.
  • Disclosure & credit2
    Catalogued by certccCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.