# CVE-2026-48189: OTRS Customer Backend improper input validation

Source: https://junglewise.ai/threats/cve-2026-48189-otrs-customer-backend-improper-input-validation  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-01. Updated: 2026-06-01  
License: CC BY 4.0 with a link back

CVE-2026-48189 · Severity: medium · CVSS 5.7 · Published 2026-06-01

A security flaw in the OTRS service management platform allows users to view customer information they are not authorized to see. This occurs when specific group-based access controls are enabled, potentially leading to the exposure of sensitive client data to unauthorized internal or external parties. Organizations using OTRS for help desk or customer support should update to the latest version to ensure data privacy and compliance.

Vendors: [OTRS AG](https://junglewise.ai/threats/vendors/otrs-ag).

## Quick answers

**Is CVE-2026-48189 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-48189 being exploited in the wild.

**How severe is CVE-2026-48189?** Medium severity, with a CVSS score of 5.7, published 1 June 2026.

**Which products and versions are affected?** OTRS AG OTRS Help Desk 7.0.X, 8.0.X, 2023.X, 2024.X, 2025.X, 2026.X before 2026.4.X.

**Is there a fix for CVE-2026-48189?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-48189 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-48189?** Check whether you run OTRS AG OTRS Help Desk at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

An improper input validation vulnerability exists within the OTRS Customer Backend module. The flaw is specifically triggered when the 'CustomerGroupSupport' feature is enabled and in use. An authenticated attacker with low privileges can exploit this lack of validation to bypass group-based access restrictions and retrieve sensitive customer data belonging to other groups. The vulnerability is tracked as CVE-2026-48189 and has been addressed in OTRS version 2026.4.X and later. The attack requires network access and minimal user interaction.

## Affected products

- OTRS AG OTRS 7.0.X, 8.0.X, 2023.X, 2024.X, 2025.X, 2026.X before 2026.4.X

## Timeline

- 2026-06-01: advisory: Initial disclosure of CVE-2026-48189
- 2026-06-01: disclosed

## References

- [https://otrs.com/release-notes/otrs-security-advisory-2026-03/](https://otrs.com/release-notes/otrs-security-advisory-2026-03/)

## Related threats

- [OTRS incorrect permissions in External Interface and ConfigItem List module](https://junglewise.ai/threats/cve-2026-48190-otrs-incorrect-permissions-in-external-interface-and-configitem)