Zammad GmbH Zammad Session Fixation Vulnerability

CISA Description

Zammad GmbH Zammad contains a session fixation vulnerability that can lead to remote code execution as the zammad user. This vulnerability can be chained with CVE-2026-102490.

Required action

Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

Notes

https://zammad.com/en/product/releases/ ; https://community.zammad.org/t/take-care-local-privilege-escalation-cve-2026-102490-is-reported-as-being-actively-exploited/21297/2 ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-102489

NVD Technical Description

Zammad versions 6.3.0 to 6.5.4 are vulnerable a session hijack vulnerability that leads to remote code execution as the zammad user. The vulnerability is also present in version 7.0.0 to version 7.1.3, but not exploitable due to environment conditions.