Auth bypass in Blackholll Loonflow
CVE-2026-121937
loonflow before r3.2.3 contains a missing authorization vulnerability in TicketFlowHistoryView that allows any authenticated user to read other users' ticket flow history by supplying a ticket UUID. Attackers can request the ticket_flow_history endpoint, which skips ticket_view_permission_check, to obtain approval comments and processor names, emails and phone numbers.
Vulnerability class: IDOR (Insecure Direct Object Reference)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 3.1 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/blackholll/loonflow/issues/591 (issue-tracking)
- hackmd.io/@hieuPenguinnn/loonflow-ticket-flow-history-idor (third-party-advisory)
- github.com/blackholll/loonflow/commit/a6495b0c2ca9e5dede8e49217a0468bcfa946de4 (patch)
- github.com/blackholll/loonflow/blob/r3.2.2/backend/apps/ticket/views.py (technical-description)
- VulnCheck Advisory: loonflow before r3.2.3 IDOR via ticket_flow_history Endpoint (third-party-advisory)
- 134c704f-9b21-4f2e-91b3-4a467353bcc0
Frequently asked questions
- What is CVE-2026-121937?
- CVE-2026-121937 is a low-severity vulnerability in Blackholll Loonflow, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 3.1/10. Published 2026-11-04.
- How severe is CVE-2026-121937?
- Low severity. CVSS v3 base score is 3.1 out of 10.