December 19, 2017 — Please read carefully and check if the version of your OTRS system is affected by this vulnerability.
Please send information regarding vulnerabilities in OTRS to: security@otrs.org
Security Advisory Details
- ID: OSA-2017-10
- Date: 2017-12-19
- Title: Session hijacking
- Severity: 7.3. High
- Product: OTRS 6.0.x, OTRS 5.0.x, OTRS 4.0.x
- Fixed in: OTRS 6.0.3, OTRS 5.0.26, OTRS 4.0.28
- URL:
- FULL CVSS v3 VECTOR: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N/E:P/RL:O/RC:C
- References:
Vulnerability Description
This advisory covers vulnerabilities discovered in the OTRS framework.
Privilege Escalation
An attacker can send a specially prepared email to an OTRS system. If this system has cookie support disabled, and a logged in agent clicks a link in this email, the session information could be leaked to external systems, allowing the attacker to take over the agent’s session.
Affected by this vulnerability are all releases of OTRS 6.0.x up to and including 6.0.2, OTRS 5.0.x up to and including 5.0.25 and OTRS 4.0.x up to and including 4.0.27.
This vulnerability is fixed in the latest versions of OTRS, and it is recommended to upgrade to the latest patch level.
Fixed releases can be found at:
Detailed information about the changes:
OTRS 6
OTRS 5
OTRS 4
However, to avoid unwanted side effects, we recommend a complete update.
Thanks to Francesco Sirocco for discovering and reporting this issue.