RCE in Flowiseai Flowise

CVE-2026-73601

Flowise versions before 3.1.3 contain a remote code execution vulnerability in the Custom MCP node when CUSTOM_MCP_PROTOCOL is set to stdio, allowing authenticated users to execute arbitrary commands by manipulating environment variables and command arguments. Attackers can abuse PYTHONWARNINGS and BROWSER environment variables with python3, or leverage the root working directory with node to bypass validation and execute system commands.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.011 (64.3th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 64th percentile — 64.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-73601: held from 0.006 to 0.011.

EPSS over last 30 days · oldest: 0.006 · newest: 0.011 · change: +0.005

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-73601?
CVE-2026-73601 is a high-severity vulnerability in Flowiseai Flowise, classified under Eval Injection. CVSS score: 8.8/10. Published 2026-08-13.
How severe is CVE-2026-73601?
High severity. CVSS v3 base score is 8.8 out of 10.