#VU8111 Deserialization of untrusted data in Apache Struts - CVE-2017-9805

Vulnerability identifier: #VU8111

Vulnerability risk: High

CVSSv4.0: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Amber

CVE-ID: CVE-2017-9805

CWE-ID: CWE-502

Exploitation vector: Remote access

Exploit availability: The vulnerability is being exploited in the wild

Vulnerable software:
Apache Struts

Software vendor:
Apache Foundation

The vulnerability allows a remote attacker to execute arbitrary code on the server.

The weakness exists due to absent filtration in XStream instance when deserializing XML data within the REST Plugin. A remote attacker can upload a specially crafted XML file to vulnerable Apache Struts installation, trigger the XStreamHandler to process malicious XML payload and execute arbitrary core on the target system.

Successful exploitation of the vulnerability is possible in case the attacker is able to upload XML.

Update to version 2.5.13.

• https://struts.apache.org/docs/s2-052.html
• https://lgtm.com/blog/apache_struts_CVE-2017-9805_announcement