December 05, 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-2017-09
- Date: 2017-12-05
- Title: Remote code execution
- Severity: 8.1 high
- Product: OTRS 6.0.x, OTRS 5.0.x, OTRS 4.0.x
- Fixed in: OTRS 6.0.2, OTRS 5.0.25, OTRS 4.0.27
- URL:
- FULL CVSS v3 VECTOR: CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H/E:P/RL:O/RC:C
- References: CVE-2017-16921
Vulnerability Description
This advisory covers vulnerabilities discovered in the OTRS framework.
Privilege Escalation
An attacker who is logged into OTRS as an agent can manipulate form parameters and execute arbitrary shell commands with the permissions of the OTRS or web server user.
Affected by this vulnerability are all releases of OTRS 6.0.x up to and including 6.0.1, OTRS 5.0.x up to and including 5.0.24 and OTRS 4.0.x up to and including 4.0.26.
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:
https://community.otrs.com/category/release-and-security-notes-en/
Detailed information about the changes:
OTRS 6
https://github.com/OTRS/otrs/commit/d12797bf1efa6722c2ba9af6d8238446c2903cd1
OTRS 5
https://github.com/OTRS/otrs/commit/d433518d7bd8e9e079af67ef9ea7079cd2f59646
OTRS 4
https://github.com/OTRS/otrs/commit/368bc37f137e6344f4db014ee2e03c38e2fc62d2
https://github.com/OTRS/otrs/commit/4043ebb2580cd8f87e7758e95bf0d77eea5c82ae
However, to avoid unwanted side effects, we recommend a complete update.
Thanks to Francesco Sirocco for discovering and reporting this issue.