Cyber Posture

CVE-2021-47794

HighPublic PoC

Published: 16 January 2026

Published
16 January 2026
Modified
21 January 2026
KEV Added
Patch
CVSS Score 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0016 36.4th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Description

ZesleCP 3.1.9 contains an authenticated remote code execution vulnerability that allows attackers to create malicious FTP accounts with shell injection payloads. Attackers can exploit the FTP account creation endpoint by injecting a reverse shell command that establishes a network connection…

more

to a specified listening host.

Mitigating Controls (NIST 800-53 r5)AI

prevent

Directly mitigates OS command injection in the FTP account creation endpoint by requiring validation and sanitization of user inputs to prevent shell payload execution.

prevent

Requires timely identification, reporting, and correction of flaws like CVE-2021-47794 through patching and integration with configuration management.

prevent

Enforces least privilege to restrict low-privilege authenticated users from accessing the vulnerable FTP account creation endpoint, blocking exploitation.

Security SummaryAI

CVE-2021-47794 is an authenticated remote code execution vulnerability in ZesleCP 3.1.9, published on 2026-01-16. The issue, tied to CWE-78 (OS Command Injection), has a CVSS v3.1 base score of 8.8 (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H). It arises in the FTP account creation endpoint, where attackers can inject shell payloads into malicious FTP accounts.

Authenticated attackers with low privileges (PR:L) can exploit the vulnerability over the network with low complexity and no user interaction required. By submitting a reverse shell command via the FTP account creation endpoint, they establish a network connection to a listener host under their control, achieving full remote code execution with high impacts on confidentiality, integrity, and availability.

Advisories and proof-of-concept exploits are available, including at https://www.exploit-db.com/exploits/50233 and https://www.vulncheck.com/advisories/zeslecp-remote-code-execution-rce-authenticated. A demonstration video exists at https://www.youtube.com/watch?v=5lTDTEBVq-0, and the vendor site is https://zeslecp.com/.

Details

CWE(s)

Affected Products

zesle
zeslecp
≤ 3.1.9

MITRE ATT&CK Enterprise TechniquesAI

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.
T1059.004 Unix Shell Execution
Adversaries may abuse Unix shell commands and scripts for execution.
Why these techniques?

CVE enables exploitation of a public-facing web application (T1190) via authenticated OS command injection in FTP account creation endpoint, facilitating Unix shell command execution (T1059.004) for RCE such as reverse shells.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

References