The ParameterInterceptor component in Apache Struts before 2.3.1.1 does not prevent access to public constructors, which allows remote attackers to create or overwrite arbitrary files via a crafted parameter that triggers the creation of a Java object.

References

• https://nvd.nist.gov/vuln/detail/CVE-2012-0393
• http://archives.neohapsis.com/archives/bugtraq/2012-01/0031.html
• http://struts.apache.org/2.x/docs/s2-008.html
• http://struts.apache.org/2.x/docs/version-notes-2311.html
• http://www.exploit-db.com/exploits/18329
• apache/struts@25e5006
• https://web.archive.org/web/20120612142634/https://sec-consult.com/files/20120104-0_Apache_Struts2_Multiple_Critical_Vulnerabilities.txt
• apache/struts@9cad25f
• https://web.archive.org/web/20140723153720/http://secunia.com/advisories/47393