CVE-2026-56274: Flowise command injection vulnerability in Custom MCP Server
Flowise
Flowise before 3.1.2 contains multiple OS command injection vulnerabilities in the Custom MCP Server feature due to incomplete command-flag validation. A patch has been released to address the issue.
disclosed CVENo confirmed exploitation, so this record is tracked as a disclosed vulnerability and not counted as an incident. It moves into the counts if CISA or the vendor confirms exploitation. Why
- CVSS
- 9.9
- EPSS
- 0.08 · top 6% · 2026-11-13
- fix status
- Fix status unknown
- first report
- 23 Jun 2026
- last update
- 23 Jun 2026
- CVE ids
Timeline · 1
Sources · 1
Advisories and databases
- 2026-06-23CVE-2026-56274: Flowise before 3.1.2 contains multiple OS command injection vulnerabilities in the Custom MCP Server feature due to incomplete…NVD · nvd.nist.gov/vuln/detail/CVE-2026-56274
Titles and links belong to their publishers. The summary above is written by gcdRadar in its own words; data is CC BY-SA 4.0.
Classification
- lane
- Patch now
- AI role
- Attack on AI
- categories
- Infrastructure vulnerability
- severity
- 2 · Disclosed vulnerability
- fix status
- Fix status unknown
- targets
- Framework / tooling
- owasp llm top 10
- LLM03:2025 Supply Chain
- mitre atlas
- no technique for these categories
- dates
- happened 23 Jun 2026 · first reported 23 Jun 2026
- origin
- NVDVulnerability record from NVD / the GitHub Advisory Database. This product uses the NVD API but is not endorsed or certified by the NVD.
- record
- confidence 0.95 · created 2026-10-18 10:04Z · updated 2026-10-18 10:04Z
Lane, AI role, categories and severity come from the classifier; the OWASP and ATLAS rows are derived from the categories. How these are assigned
Copy a brief
This record as a short Markdown brief, for a ticket, a chat or a coding agent.
the brief as text
# CVE-2026-56274: Flowise command injection vulnerability in Custom MCP Server https://gcdradar.vercel.app/incidents/cve-2026-56274-flowise-command-injection-vulnerability-in-cu · AIR-2026-1126 · closed 2026-06-23 - Lane: Patch now - Severity: 2 (Disclosed vulnerability) - Fix status: Fix status unknown - First reported: 2026-06-23 - AI role: Attack on AI - Products: Flowise - CVE ids: CVE-2026-56274 - CVSS: 9.9 ## Summary Flowise before 3.1.2 contains multiple OS command injection vulnerabilities in the Custom MCP Server feature due to incomplete command-flag validation. A patch has been released to address the issue. ## What to do No action recorded; read the sources below and the vendor's advisory. ## Latest updates - 2026-06-23: CVE-2026-56274: Flowise before 3.1.2 contains multiple OS command injection vulnerabilities in the Custom MCP Server feature due to incomplete… (https://nvd.nist.gov/vuln/detail/CVE-2026-56274) ## Sources - 2026-06-23 NVD: CVE-2026-56274: Flowise before 3.1.2 contains multiple OS command injection vulnerabilities in the Custom MCP Server feature due to incomplete… https://nvd.nist.gov/vuln/detail/CVE-2026-56274 Verify against the vendor's advisory before changing production. Data CC BY-SA 4.0, https://gcdradar.vercel.app.
Related
- closed9.8Flowise Weak Hardcoded JWT Secrets in Flowise Authentication
Patch now · Disclosed · since 12 Jul 2026 · CVE-2026-56271
AI - closed6.5Flowise Path Traversal in Flowise Vector Store Implementations
Patch now · Disclosed · since 8 Jul 2026 · CVE-2026-56273
AI - closed9.3Flowise CVE-2026-56278: Flowise uses a hardcoded default session secret enabling authentication bypass
Patch now · Disclosed · since 30 Jun 2026 · CVE-2026-56278
AI - closed6.9Flowise CVE-2026-56277: Flowise text-to-speech endpoint suffers from improper CORS configuration
Patch now · Disclosed · since 30 Jun 2026 · CVE-2026-56277
AI - closed5.0Flowise CVE-2026-58057: Flowise custom MCP stdio environment variable bypass leads to RCE
Patch now · Disclosed · since 28 Jun 2026 · CVE-2026-58057
AI - closed9.3Flowise Flowise Authentication Bypass Vulnerability CVE-2025-71327
Patch now · Disclosed · since 25 Jun 2026 · CVE-2025-71327
AI