Vulnerability · Published Nov 4, 2026 · Assigned by VulnCheck

CVE-2026-121937loonflow before r3.2.3 IDOR via ticket_flow_history Endpoint

Low 3.1

In plain English

A low-severity authorization bypass via user-controlled key in loonflow from blackholll. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 25% of all known vulnerabilities).

Severity (CVSS 3.1)3.1Low

Exploit odds (30 days)0.3%top 74.9% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

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.

Affected products (as reported)

Vendor	Product	Versions
blackholll	loonflow	0 – before r3.2.3

Weakness: CWE-639 · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N

References

https://github.com/blackholll/loonflow/issues/591 issue-tracking
https://hackmd.io/@hieuPenguinnn/loonflow-ticket-flow-history-idor third-party-advisory
https://github.com/blackholll/loonflow/commit/a6495b0c2ca9e5dede8e49217a0468bcfa946de4 patch
https://github.com/blackholll/loonflow/blob/r3.2.2/backend/apps/ticket/views.py#L265-L286 technical-description
VulnCheck Advisory: loonflow before r3.2.3 IDOR via ticket_flow_history Endpoint third-party-advisory
https://hackmd.io/@hieuPenguinnn/cve-2026-121937-loonflow-ticket-flow-history-idor exploit