{"cve":"CVE-2026-78359","nvd":{"published":"2026-10-12T07:16:37.423","modified":"2026-10-15T20:38:44.050","status":"Deferred","description":"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.\n\nThis 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.\n\nThe vulnerability does not allow unauthenticated users to create customer accounts. Exploitation requires permissions to create or modify customer users.\n\nThis issue affects OTRS:\n\n  *  7.0.X\n  *  8.0.X\n  *  2023.X\n  *  2024.X\n  *  2025.X\n  *  2026.X before 2026.7.X\n\nPlease note that ((OTRS)) Community Edition 6.x and before are vulnerable. Products based on the ((OTRS)) Community Edition also very likely to be affected","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N","score":5.4},"cwes":["CWE-694","CWE-706"],"references":["https://otrs.com/release-notes/otrs-security-advisory-2026-16/"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:58:52.678897993+00:00"},"epss":{"cve":"CVE-2026-78359","score":0.00164,"percentile":0.05529,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}