Security readout for executives and security teams
Plain-English summary
Flowise instances before 3.0.8 can let malicious content entered through chat or returned by agent workflows run in another user’s browser. The main business risk is session or cookie theft and unauthorized actions under a victim’s account after interaction with affected content.
Executive priority
Treat this as a near-term remediation item, especially for public or customer-facing Flowise deployments. It is not presented as actively exploited, but session theft risk justifies prompt upgrade and exposure review.
Technical view
This is a cross-site scripting flaw in Flowise before 3.0.8 caused by insufficient filtering of chat messages and custom agent function output. The CVSS 3.1 score is 6.1, with network reachability, low attack complexity, required user interaction, changed scope, and low confidentiality and integrity impact.
Likely exposure
Exposure is most likely where Flowise is internet-accessible, accepts untrusted chat input, or runs custom agent workflows that return external content to users. The bundle identifies Flowise before 3.0.8 as affected.
Exploitation context
The provided sources do not identify active exploitation, and the CVE is not listed as KEV in the bundle. Exploitation requires a victim to view or interact with affected rendered content in Flowise.
Researcher notes
Evidence is limited to the supplied CVE, GHSA, and VulnCheck descriptions. Validate exact affected builds and fixed behavior against the vendor advisory before making version-specific assertions beyond Flowise before 3.0.8.
Mitigation direction
- Upgrade Flowise to version 3.0.8 or later.
- Review the vendor advisory for supported remediation guidance.
- Restrict untrusted access to affected chat interfaces until upgraded.
- Review custom agent functions that render external or user-controlled content.
- Rotate sessions if suspicious browser script execution is suspected.
Validation and detection
- Inventory Flowise deployments and record running versions.
- Confirm affected systems are not below version 3.0.8.
- Review public routes exposing Flowise chat to untrusted users.
- Audit custom agent workflows returning external website content.
- Check logs for suspicious chat content around user sessions.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-80: User-session and phishing behavior lookup
Client-side and session-facing weaknesses should be reviewed alongside initial-access and user-execution behaviors. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2025-71331 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 6.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
2 official scoresWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N2.82.7VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N——VulnCheckVulnerability scoring details
Base CVSS 4.0 score
5.1MediumVector: 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
Base CVSS 3.1 score
6.1MediumVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- GHSA Advisory GHSA-4fr9-3x69-36wvCVE reference, VulnCheck · vendor-advisory
- VulnCheck Advisory: Flowise - Cross-Site Scripting in Chat Messages and Agent WorkflowsCVE reference, VulnCheck · third-party-advisory
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)
Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS) represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.