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

Status: published. Published: 2026-11-04. Updated: 2026-11-04.

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.

## Remediation

- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: CNA: VulnCheck) — https://github.com/blackholll/loonflow/commit/a6495b0c2ca9e5dede8e49217a0468bcfa946de4

## Affected products and versions

- blackholll / loonflow (blackholll/loonflow): ≥ 0; < r3.2.3 (affected, custom). Source: CNA: VulnCheck

## Severity and prioritization

- CVSS 4.0: 2.3 (low); CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N; source: CNA: VulnCheck

- CVSS 3.1: 3.1 (low); CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N; source: CNA: VulnCheck

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-639

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://github.com/blackholll/loonflow/issues/591 (CNA: VulnCheck; issue-tracking)

- https://hackmd.io/@hieuPenguinnn/loonflow-ticket-flow-history-idor (CNA: VulnCheck; third-party-advisory)

- https://github.com/blackholll/loonflow/commit/a6495b0c2ca9e5dede8e49217a0468bcfa946de4 (CNA: VulnCheck; patch)

- https://github.com/blackholll/loonflow/blob/r3.2.2/backend/apps/ticket/views.py#L265-L286 (CNA: VulnCheck; technical-description)

- https://www.vulncheck.com/advisories/loonflow-before-r3-2.3-idor-via-ticket-flow-history-endpoint (CNA: VulnCheck; third-party-advisory)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-121937; retrieved 2026-11-04; source updated 2026-11-04

Revision: 739b1fdd844d5eb8cd85cac0091552d338afb8fe912fb5058d406a23f5d9864d

Canonical: https://y2.dev/cve/CVE-2026-121937

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