CVE-2026-69254: Flowise: RCE via NodeVM Sandbox Escape in executeJavaScriptCode() nodeVMOptions Override

Should you act?

Critical, preconditions apply

Severe if exploited, but exploitation needs conditions that may not apply to you. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• Not in CISA KEV, but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
• EPSS 0.7%, percentile 52: FIRST’s model estimates a 0.7% chance of exploitation activity in the next 30 days, higher than 52% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
• Needs an account (low (any account)). Exposure depends on who can log in.
• Only applies if your dependency tree includes flowise (npm) <= 3.1.2, fixed in 3.1.3; flowise-components (npm) <= 3.1.2, fixed in 3.1.3. Check your lockfile, including transitive dependencies.

What it is

Flowise is a drag & drop user interface to build a customized large language model flow. Prior to 3.1.3, executeJavaScriptCode() accepted caller-provided nodeVMOptions and merged them over the default NodeVM security settings in packages/components/src/utils.ts. An authenticated attacker reaching packages/server/src/routes/node-custom-functions/index.ts could run a custom function that imported flowise-components/dist/src/utils.js, called executeJavaScriptCode() again with nodeVMOptions.require.builtin set to allow all built-in modules, and then required childprocess to execute arbitrary system commands as root on the Flowise server. This issue is fixed in version 3.1.3.

From the GitHub advisory

Summary A sandbox escape vulnerability in executeJavaScriptCode() allows any authenticated user to execute arbitrary system commands as root on the Flowise server. The function accepts caller-provided nodeVMOptions that override the default sandbox security settings via JavaScript's spread operator, allowing an attacker to re-enable blocked modules like childprocess and fs.

Details The vulnerability is in packages/components/src/utils.ts at line 1755:

The spread operator allows any caller to override require.builtin with [""], which permits all Node.js built-in modules including childprocess.

Taint 01: Route Registration packages/server/src/routes/node-custom-functions/index.ts (line 8)

Taint 02: Controller executeCustomFunction() passes req.body to service — packages/server/src/controllers/nodes/index.ts (line 90)

Weakness type: CWE-94.

Product: flowise (npm) · Assigned by: GitHub_M · Published: 2026-08-04

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: low
• Attack requirements: none
• Privileges required: low (any account)
• User interaction: none

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
• CISA SSVC assessment: exploitation poc, automatable no, technical impact total.
• FIRST EPSS (model of 2026-10-21): 0.69% probability of exploitation activity in the next 30 days; percentile 52.

Timeline

• 2026-08-04 — CVE record last updated
• 2026-08-04 — CVE record published by GitHub_M
• 2026-08-04 — GitHub-reviewed advisory GHSA-3769-jgqc-cxm7 published (critical)

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vulnerability records

1. GitHub Advisory GHSA-3769-jgqc-cxm7 github.com
2. CVE.org record CVE-2026-69254 cve.org
3. NVD entry CVE-2026-69254 nvd.nist.gov

Other references from the CVE record and advisory

1. github.com github.com
2. github.com github.com
3. github.com github.com
4. github.com github.com

Critical npm advisories · Today’s Security Digest