CVE-2026-33760

HIGH 8.8

Published 2026-06-23 · Last modified 2026-06-24

Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to 1.9.0, Langflow's /api/v1/monitor router exposes 7 endpoints that perform read, write, and delete operations on user-owned resources — messages, sessions, build artifacts, and LLM transaction logs — without verifying that the authenticated requester owns the targeted resource. Any authenticated user can read, modify, rename, or permanently delete another user's data by supplying the target's resource ID or flow_id. This is a classic IDOR/BOLA vulnerability. Notably, the same source file (monitor.py) contains one correctly-implemented endpoint that uses an ownership check, demonstrating the correct pattern was known but inconsistently applied. This vulnerability is fixed in 1.9.0.

ELEVATED IMPACT

Severe if exploited (CVSS 8.8), but no known exploitation and low modeled probability. Patch on a normal cadence.

Exploitation likelihood

0.3%chance of exploitation in 30 days · 21st percentile

○ In CISA KEV ○ Public exploit / PoC

Impact if exploited

8.8CVSS 3.1 · HIGH

ConfidentialityHigh
IntegrityHigh
AvailabilityHigh

What an attacker needs

✓Access: Reachable over the network — no local access needed
⚠Privileges: Requires a low-privilege account
✓User interaction: No user interaction needed
✓Complexity: No special conditions — reliably repeatable

✓ lowers the bar for an attacker · ⚠ raises it

Proof of concept & exploit code

reference https://github.com/langflow-ai/langflow/security/advisories/GHSA-9c59-2mvc-vfr8
github-search Search GitHub for public PoC repos

Test against your own equipment

curl -s https://vulnpedia.com/cve/CVE-2026-33760/poc.jsonMachine-readable PoC index for this CVE (for automation).

Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-33760/poc.json

Affected

Vendors Langflow Ai Langflow

Products Langflow

Weakness (CWE)

CWE-639: : Authorization Bypass Through User-Controlled Key

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Known Affected Software Configurations

Vendor	Product	Version range
Langflow	Langflow	< 1.9.0

All CVSS metrics

HIGH 8.8 v3.1 · CNA Primary
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
HIGH 8.8 v3.1 · NVD Secondary
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

References

Exploits & PoC

https://github.com/langflow-ai/langflow/security/advisories/GHSA-9c59-2mvc-vfr8 x_refsource_CONFIRMExploitVendor Advisory

Sources: NVD · CVE.org · EPSS