CVE-2021-42751

MEDIUM

ThingsBoard 3.3.1 - Authenticated Stored Cross-Site Scripting in Rule Engine Description

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2021-42751. PoCs published by Steffen Langenfeld.

AI-analyzed exploit summary This exploit demonstrates a stored XSS vulnerability in ThingsBoard 3.3.1, where a malicious script injected into the description field of a rule node executes when hovered over in the editor.

Description

A cross-site scripting (XSS) vulnerability in Rule Engine in ThingsBoard 3.3.1 allows remote attackers (with administrative access) to inject arbitrary JavaScript within the description of a rule node.

Exploits (1)

exploitdb WORKING POC
by Steffen Langenfeld · textwebappsmultiple
https://www.exploit-db.com/exploits/51004

This exploit demonstrates a stored XSS vulnerability in ThingsBoard 3.3.1, where a malicious script injected into the description field of a rule node executes when hovered over in the editor.

Classification
Working Poc 100%
Attack Type
Xss
Complexity
Trivial
Reliability
Reliable
Target: ThingsBoard 3.3.1
Auth required
Prerequisites: Access to create or edit rule nodes in ThingsBoard
devstral-2 · analyzed Feb 16, 2026 Full analysis →

References (2)

Core 2
Core References
Product, Third Party Advisory x_refsource_misc
https://github.com/thingsboard/thingsboard
Exploit, Third Party Advisory, VDB Entry x_refsource_misc
https://packetstormsecurity.com/files/167999/Thingsboard-3.3.1-Cross-Site-Scripting.html

Scores

CVSS v3 4.8
EPSS 0.0233
EPSS Percentile 81.3%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N

Details

CWE
CWE-79
Status published
Products (1)
thingsboard/thingsboard 3.3.1
Published Aug 12, 2022
Tracked Since Feb 18, 2026