CVE-2020-2509

CRITICAL KEV RANSOMWARE

QTS < 4.2.6 - OS Command Injection

Title source: llm
STIX 2.1

Exploitation Summary

CVE-2020-2509 is actively exploited and listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added April 11, 2022, with confirmed use in ransomware campaigns. EIP tracks 1 public exploit from researchers including jbaines-r7.

AI-analyzed exploit summary This exploit targets a QNAP QTS vulnerability by sending HTTP GET requests to `/cgi-bin/qnapmsg.cgi?lang=xxx`, causing the device to download an XML file from `update.qnap.com` via insecure HTTP. An attacker can redirect this request to serve a malicious XML file, leading to a reverse shell via command injection in the `system` call.

Description

A command injection vulnerability has been reported to affect QTS and QuTS hero. If exploited, this vulnerability allows attackers to execute arbitrary commands in a compromised application. We have already fixed this vulnerability in the following versions: QTS 4.5.2.1566 Build 20210202 and later QTS 4.5.1.1495 Build 20201123 and later QTS 4.3.6.1620 Build 20210322 and later QTS 4.3.4.1632 Build 20210324 and later QTS 4.3.3.1624 Build 20210416 and later QTS 4.2.6 Build 20210327 and later QuTS hero h4.5.1.1491 build 20201119 and later

Exploits (1)

nomisec WORKING POC 14 stars
by jbaines-r7 · remote
https://github.com/jbaines-r7/overkill

This exploit targets a QNAP QTS vulnerability by sending HTTP GET requests to `/cgi-bin/qnapmsg.cgi?lang=xxx`, causing the device to download an XML file from `update.qnap.com` via insecure HTTP. An attacker can redirect this request to serve a malicious XML file, leading to a reverse shell via command injection in the `system` call.

Classification
Working Poc 100%
Attack Type
Rce
Complexity
Moderate
Reliability
Reliable
Target: QNAP QTS (unknown version, patched in November 2020 and April 2021)
No auth needed
Prerequisites: Ability to redirect `update.qnap.com` to an attacker-controlled server · Network access to the target QNAP device
devstral-2 · analyzed Feb 16, 2026 Full analysis →

References (2)

Core 2

Scores

CVSS v3 9.8
EPSS 0.3417
EPSS Percentile 98.2%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation active
Automatable yes
Technical Impact total

Details

CISA KEV 2022-04-11
VulnCheck KEV 2022-04-11
InTheWild.io 2021-04-23
ENISA EUVD EUVD-2020-22302
Ransomware Use Confirmed
CWE
CWE-78 CWE-77
Status published
Products (36)
qnap/qts 4.2.6 (10 CPE variants)
qnap/qts 4.3.3.0174
qnap/qts 4.3.3.0868
qnap/qts 4.3.3.0998
qnap/qts 4.3.3.1051
qnap/qts 4.3.3.1098
qnap/qts 4.3.3.1161
qnap/qts 4.3.3.1252
qnap/qts 4.3.3.1315
qnap/qts 4.3.3.1386
... and 26 more
Published Apr 17, 2021
KEV Added Apr 11, 2022
Tracked Since Feb 18, 2026