CVE-2026-102489
Zammad GmbH Zammad Session Fixation Vulnerability
Zammad GmbH Zammad
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.
Exploitation status
CISA Known Exploited Vulnerabilities
Listed by CISA on 2 October 2026. US federal agencies were required to remediate it by 5 October 2026.
EPSS — exploitation probability
FIRST puts the probability of exploitation activity in the next 30 days at 1.3%, which is higher than 68.6% of all scored vulnerabilities. EPSS is a forecast of activity, not a measure of severity, and it is rescored daily.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Frequently asked questions
Is CVE-2026-102489 being exploited by ransomware groups?
No ransomware group in this database is currently recorded as exploiting CVE-2026-102489.
What does CVE-2026-102489 affect?
CVE-2026-102489 affects Zammad GmbH Zammad. 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.
How severe is CVE-2026-102489?
CVE-2026-102489 is rated CRITICAL with a CVSS base score of 9.8. EPSS puts the probability of exploitation in the next 30 days at 1.3%, higher than 68.6% of all scored vulnerabilities. It is listed in the CISA Known Exploited Vulnerabilities catalog, with a federal remediation deadline of 5 October 2026.
How should organisations respond to CVE-2026-102489?
Apply the vendor patch for Zammad GmbH Zammad as the first priority, and treat any internet-facing instance as the most urgent. Because this vulnerability is associated with ransomware activity, also review whether the affected systems were reachable before patching, rather than assuming that patching alone closes the incident.