Cyber Resilience

CVE-2021-27860

Fatpipeinc Ipvpn Firmware 10.1.2 … 9.1.2

CISA KEVActive ExploitationEUVD ExploitedPublic PoC
Published
08 December 2021
Modified
24 October 2025
KEV Added
10 January 2022
Patch / advisory
CVSS Score v3.1 9.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.40 98th percentile
Risk Priority 97 floored blend · peak EPSS

Summary

CVE-2021-27860 is a critical-severity Unrestricted Upload of File with Dangerous Type (CWE-434) vulnerability in Fatpipeinc Ipvpn Firmware. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 2% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog; a public proof-of-concept is referenced.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

The vulnerability CVE-2021-27860 is an unrestricted file upload flaw (CWE-434) in the web management interface of FatPipe WARP, IPVPN, and MPVPN software prior to versions 10.1.2r60p92 and 10.2.2r44p1. It is tracked under FatPipe advisory FPSA006 and carries a CVSS 3.1 score of 9.8.

A remote unauthenticated attacker can exploit the issue over the network to upload a file to any location on the filesystem, enabling arbitrary code execution or full system compromise.

FatPipe's advisory and related notices from CISA and the FBI IC3 direct administrators to upgrade to the fixed releases listed above. The CVE is also cataloged in CISA's Known Exploited Vulnerabilities list, confirming observed in-the-wild exploitation.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

A vulnerability in the web management interface of FatPipe WARP, IPVPN, and MPVPN software prior to versions 10.1.2r60p92 and 10.2.2r44p1 allows a remote, unauthenticated attacker to upload a file to any location on the filesystem. The FatPipe advisory identifier for…

more

this vulnerability is FPSA006.

CWE(s)
KEV Date Added
10 January 2022

Related Threats

MITRE ATT&CK Enterprise Techniques

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1505 Server Software Component Persistence
Adversaries may abuse legitimate extensible development features of servers to establish persistent access to systems.
T1505.003 Web Shell Persistence
Adversaries may backdoor web servers with web shells to establish persistent access to systems.
T1059 Command and Scripting Interpreter Execution
Adversaries may abuse command and script interpreters to execute commands, scripts, or binaries.
T1105 Ingress Tool Transfer Command And Control
Adversaries may transfer tools or other files from an external system into a compromised environment.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2020-13671Shared CWE-434both on KEV
CVE-2017-11357Shared CWE-434both on KEV
CVE-2025-52691Shared CWE-434both on KEV
CVE-2026-56290Shared CWE-434both on KEV
CVE-2020-8260Shared CWE-434both on KEV
CVE-2016-3088Shared CWE-434both on KEV
CVE-2021-26828Shared CWE-434both on KEV
CVE-2017-12615Shared CWE-434both on KEV
CVE-2018-4063Shared CWE-434both on KEV
CVE-2024-7694Shared CWE-434both on KEV

Affected Assets

fatpipeinc
ipvpn firmware
10.1.2, 10.2.2, 5.2.0, 6.1.2, 7.1.2
fatpipeinc
warp firmware
10.1.2, 10.2.2, 5.2.0, 6.1.2, 7.1.2
fatpipeinc
mpvpn firmware
10.1.2, 10.2.2, 5.2.0, 6.1.2, 7.1.2

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V5.1.1

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-434

Requiring identifiable owners for portable devices reduces the attack surface for unrestricted uploads of dangerous file types via anonymous media.

addresses: CWE-434

Dangerous file uploads can be detonated in the chamber to determine malice before any production write or execution occurs.

addresses: CWE-434

Prevents unrestricted writing of arbitrary or malicious firmware by keeping hardware write-protect enabled except under tightly controlled manual procedures.

addresses: CWE-434

Scans files from external sources on download/open/execute, blocking unrestricted uploads of dangerous file types.

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.

PR.PS-05 mostly match
prevents

Restricting execution of unauthorized software directly blocks dangerous uploaded files from running.

PR.PS-01 partial match
prevents

Hardened configuration baselines can enforce allowed file types and processing rules.

PR.PS-06 partial match
prevents

Secure development practices include input validation and file-type restrictions that prevent this weakness.

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.

finds

Configuration and acceptance testing verify that file-upload handling enforces allowed types and does not permit dangerous content to be stored or executed.

prevents

Secure-coding guidelines and security testing explicitly address restrictions on allowed file types and upload handling, reducing the risk that dangerous file uploads are accepted without validation.

prevents

Mandated testing for malicious content and known vulnerabilities reduces the likelihood that an outsourced component will contain or accept dangerous file types that could later be uploaded or executed.

mitigates

Application allow-listing and pre-use scanning of received files directly blocks the introduction of executable content that has not been vetted, eliminating the primary vector for unrestricted dangerous file uploads.

References