CVE-2026-73601 Flowise before 3.1.3 Remote Code Execution via Custom MCP
Authenticated attackers can execute arbitrary system commands in Flowise by manipulating environment variables in the Custom MCP node when stdio protocol is enabled.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-73601?
CVE-2026-73601 is a critical command injection vulnerability in Flowiseai Flowise, published on 13 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
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.
Weakness: CWE-95
Which versions are affected by CVE-2026-73601?
It affects 1 product.
Products include Flowiseai Flowise.
How do I fix CVE-2026-73601?
No fix has been published for CVE-2026-73601 yet. Limit exposure of the affected software until one is available.
Upgrade, and pass arguments to programs as a list instead of through a shell. More about Command injection.
Is CVE-2026-73601 being exploited?
There is no known exploitation of CVE-2026-73601 in the wild and no public exploit code.
Other vulnerabilities in Flowiseai Flowise
- CVE-2025-71338 Flowise through 2.2.7 - Arbitrary File Write to Remote Code Execution via document-store API
- CVE-2026-40933 Flowise: Authenticated RCE Via MCP Adapters
- CVE-2025-61913 Flowise is vulnerable to arbitrary file read, arbitrary file write
- CVE-2025-59528 Flowise has Remote Code Execution vulnerability
- CVE-2026-52098 Code injection in n/a
Sources
Also known as GHSA-g98q-rm45-q9h8, GHSA-m2vg-4724-xj8g.