CVE-2026-58057: low-severity vulnerability in Flowise
Flowise - Custom MCP Environment Variable Denylist Bypass via Case Sensitivity
Published · Updated
28Vexday Risk Score
No sign of exploitation. It has a public proof of concept.
ssvc Attendcvss 2.3epss 1.6%
from disclosure to weapon9 days
Published on NVDJun 28
1st PoC+9d
exploitation probability
1.6%top 26% of all CVEs
observed exploitation
nono source reports it
3 public exploit(s)
Flowise before 3.1.3 validates Custom MCP stdio environment variables against a denylist using a case-sensitive comparison, so on Windows, where environment names are case-insensitive, supplying 'node_options' bypasses the NODE_OPTIONS denylist entry. An authenticated user who can configure a Custom MCP node can thereby inject NODE_OPTIONS --require and execute arbitrary code in the Flowise server context.
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N
Affected products
Flowise · Flowisepublic PoCs found — 3
exploitdbwww.exploit-db.com/exploits/52623unverifiedgithubgithub.com/CerberusMrXi/Flowise-CVE-2026-58057-exploit★ 1cve_referencegithub.com/bikini/exploitarium/tree/main/flowise-mcp-env-case-bypass-pocunverified⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
Related CVEs — Flowise
In the same product, most dangerous first.
CVE-2026-56274HIGHFlowise - Remote Code Execution via MCP Security Bypass in validateCommandFlags and validateArgsForLocalFileAccessEPSS 7.5%CVE-2025-71334CRITICALFlowise - Arbitrary File Access via Missing Chat Flow ID ValidationEPSS 4.4%CVE-2026-56270HIGHFlowise - Unauthenticated OAuth Secrets Disclosure via /api/v1/loginmethod EndpointEPSS 2.0%CVE-2025-71324HIGHFlowise - Arbitrary File Read via chatId ParameterEPSS 1.6%CVE-2025-71338CRITICALFlowise through 2.2.7 - Arbitrary File Write to Remote Code Execution via document-store APIEPSS 1.2%CVE-2025-71336CRITICALFlowise - Unsandboxed Remote Code Execution via Custom MCPEPSS 1.1%