# CVE-2025-71331 — Flowise

> As of 2026-06-20, CVE-2025-71331 is a MEDIUM-severity vulnerability in Flowise, CVSS v3.1 6.1. No Threadlinqs-tracked threat campaign has been attributed to CVE-2025-71331 as of 2026-06-20; the identifier is re-checked against the Threadlinqs threat corpus on every daily ingest.

**Last updated:** 2026-06-20

## What is CVE-2025-71331?

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., ) 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.

The record classifies CVE-2025-71331 under weakness class [CWE-80](https://cwe.mitre.org/data/definitions/80.html). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs a user to take an action first. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 107 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 6.1 — MEDIUM (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N`)
- **CVSS v4.0 base score:** 5.1 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N`)
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 3.1/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-06-20

## Is CVE-2025-71331 being exploited?

It currently carries a trending score of 30 in the Threadlinqs vulnerability feed.

## Affected products and versions

- **Flowise**: Flowise

## How to fix CVE-2025-71331

No vendor patch reference has been recorded for CVE-2025-71331 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2025-71331

No threat campaign in the Threadlinqs corpus currently references CVE-2025-71331, in its CVE list or as an indicator. The linkage is recomputed from the live corpus on every daily ingest, so this section fills in as soon as a tracked campaign cites the identifier.

## Sources

Enriched from CVE.org, GitHub Security Advisories, NVD. Last verified by Threadlinqs on 2026-06-21. This product uses the NVD API but is not endorsed or certified by the NVD.

**Vendor advisory and patch**

- [github.com — vendor advisory](https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-4fr9-3x69-36wv)

**Third-party advisory**

- [vulncheck.com — third party advisory](https://www.vulncheck.com/advisories/flowise-cross-site-scripting-in-chat-messages-and-agent-workflows)

Canonical: https://intel.threadlinqs.com/cve/CVE-2025-71331
Full detection coverage and IOCs for threats exploiting CVE-2025-71331 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp