CVE-2026-21866

🔶 medium

Summary

Dify is an open-source LLM app development platform. Prior to 1.11.2, Dify is vulnerable to a stored XSS issue when rendering Mermaid diagrams within chats. This occurs because Dify’s default Mermaid configuration uses securityLevel: loose, which allows potentially unsafe content to execute. This vulnerability is fixed in 1.11.2.

CVSS Score

5.4

Medium

EPSS Score

0.0

Exploit Probability

Published Date

2026-03-03

First Seen: 2026-03-04

📊 Relative Risk Intelligence

This CVE is Lower Risk - more severe than 22.9% of all 321,566 vulnerabilities in our database.

#247,909

Below average severity

Severity Percentile

🎯 CISA SSVC Assessment Updated: Mar 4, 2026

🔍 Exploitation Status

Poc

Proof-of-concept available

⚙️ Automatable

Requires human interaction

💥 Technical Impact

Partial

Limited system impact

SSVC data provided by CISA

Last Modified 2026-03-05

Source NVD 🔗

CVSS Vector 3.1 CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

CVSS Vector 4.0

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CWE IDs (Weakness Types)

CWE-79

📦 Affected Products 1

Vendor	Product	Status	Affected Versions
dify	dify	Affected	< 1.11.2

🔗 References 3

https://github.com/langgenius/dify/commit/ae17537470...

Patch

https://github.com/langgenius/dify/pull/29811

Issue Tracking Patch

https://github.com/langgenius/dify/security/advisori...

Exploit Vendor Advisory

🔗 Related CVEs 6

CVE ID	Severity	CVSS	EPSS	Summary	Published
CVE-2026-41947	⚠️ high	7.4	0.0	Dify version 1.14.1 and prior contains an authorization bypass vulnerability that allows authenticated editor users to s...	2026-05-18
CVE-2026-41948	⚠️ high	7.7	0.1	Dify version 1.14.1 and prior contain a path traversal vulnerability that allows authenticated users to manipulate reque...	2026-05-18
CVE-2026-41949	🔶 medium	5.9	0.0	Dify version 1.14.1 and prior contain an authorization bypass vulnerability in the file preview endpoint that allows any...	2026-05-18
CVE-2026-28288	🔶 medium	5.3	0.0	Dify is an open-source LLM app development platform. Prior to 1.9.0, responses from the Dify API to existing and non-exi...	2026-02-27
CVE-2026-26023	🔶 medium	6.1	0.0	Dify is an open-source LLM app development platform. Prior to 1.13.0, a cross site scripting vulnerability has been foun...	2026-02-11
CVE-2025-67732	🔶 medium	6.5	0.0	Dify is an open-source LLM app development platform. Prior to version 1.11.0, the API key is exposed in plaintext to the...	2026-01-05

These CVEs affect the same products