OTRS GmbH up to 2026.6 Customer User Identity Uniqueness Check permission

Summaryinfo

A vulnerability categorized as problematic has been discovered in OTRS GmbH OTRS. Affected is an unknown function of the component Customer User Identity Uniqueness Check. The manipulation results in permission. This vulnerability is cataloged as CVE-2026-78359. The attack may be launched remotely. There is no exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in OTRS GmbH OTRS. Affected is an unknown functionality of the component Customer User Identity Uniqueness Check. The manipulation with an unknown input leads to a permission vulnerability. CWE is classifying the issue as CWE-275. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

OTRS does not sufficiently enforce the uniqueness of customer user identities across multiple configured CustomerUser backends. When multiple backends, such as a database and LDAP, are configured, the uniqueness check for customer user email addresses is performed only within the selected backend. As a result, an authenticated user with permission to create or modify customer users may create a customer user whose email address is already assigned to a customer user in another backend. This can result in multiple customer user records representing the same communication identity. Depending on the affected workflow and backend resolution, customer-related information or email communication may subsequently be associated with or exposed to the wrong customer user. The vulnerability does not allow unauthenticated users to create customer accounts. Exploitation requires permissions to create or modify customer users. This issue affects OTRS: * 7.0.X * 8.0.X * 2023.X * 2024.X * 2025.X * 2026.X before 2026.7.X Please note that ((OTRS)) Community Edition 6.x and before are vulnerable. Products based on the ((OTRS)) Community Edition also very likely to be affected

The advisory is shared for download at otrs.com. This vulnerability is traded as CVE-2026-78359 since 08/24/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. Additional levels of successful authentication are needed for exploitation. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1222.

Upgrading to version 2026.7.X eliminates this vulnerability.

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Productinfo

Type

• Service Management Software

Vendor

• OTRS GmbH

Name

• OTRS

Version

• 6
• 7.0.X
• 8.0.X
• 2023
• 2023.X
• 2024
• 2024.X
• 2025
• 2025.X
• 2026.6

License

• open-source

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

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Entryinfo

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