Medium severity · published Jun 20, 2026
CVE-2025-71331
Flowise - Cross-Site Scripting in Chat Messages and Agent Workflows
6.1
CVSS
0.3%
EPSS
No
On KEV
Description
Flowise before 3.0.8 contains a cross-site scripting (XSS) vulnerability caused by insufficient input filtering in chat messages and custom agent functions. An attacker can inject malicious JavaScript by sending an iframe payload (e.g., <iframe src="javascript:alert(document.cookie)">) in a chat box, or by having a custom agent function return an XSS payload from an external website. The injected script executes in the victim's browser, enabling theft of cookies and session data.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 26% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FL
Flowise · Flowise
before 3.0.8 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-71331
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-71331
Exploit
https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-4fr9-3x69-36wv
Third Party Advisory
https://www.vulncheck.com/advisories/flowise-cross-site-scripting-in-chat-messages-and-agent-workflows
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