The fix issued for CVE-2020-17530 was incomplete. So from Apache Struts 2.0.0 to 2.5.29, still some of the tag’s attributes could perform a double evaluation if a developer applied forced OGNL evaluation by using the %{...} syntax. Using forced OGNL evaluation on untrusted user input can lead to a Remote Code Execution and security degradation.

Forced OGNL evaluation, when evaluated on raw user input in tag attributes, may lead to remote code execution. Affected software : Apache Struts 2.0.0 - Struts 2.5.25.

An access permission override in Apache Struts 2.0.0 to 2.5.20 may cause a Denial of Service when performing a file upload.

Apache Struts 2.0.0 to 2.5.20 forced double OGNL evaluation, when evaluated on raw user input in tag attributes, may lead to remote code execution.

The Apache Struts REST Plugin is using XStream library which is vulnerable and allow perform a DoS attack when using a malicious request with specially crafted XML payload. Upgrade to the Apache Struts version 2.5.16 and switch to an optional Jackson XML handler as described here http://struts.apache.org/plugins/rest/#custom-contenttypehandlers. Another option is to implement a custom XML handler based on the Jackson XML handler from the Apache Struts 2.5.16.

In Apache Struts 2.5 to 2.5.14, the REST Plugin is using an outdated JSON-lib library which is vulnerable and allow perform a DoS attack using malicious request with specially crafted JSON payload.

In Apache Struts 2.3.7 through 2.3.33 and 2.5 through 2.5.12, if an application allows entering a URL in a form field and built-in URLValidator is used, it is possible to prepare a special URL which will be used to overload server process when performing validation of the URL. NOTE: this vulnerability exists because of an incomplete fix for S2-047 / CVE-2017-7672.

The REST Plugin in Apache Struts 2.1.x, 2.3.7 through 2.3.33 and 2.5 through 2.5.12 is using an outdated XStream library which is vulnerable and allow perform a DoS attack using malicious request with specially crafted XML payload.

In Apache Struts 2.0.0 through 2.3.33 and 2.5 through 2.5.10.1, using an unintentional expression in a Freemarker tag instead of string literals can lead to a RCE attack.

In Apache Struts 2.5 through 2.5.5, if an application allows entering a URL in a form field and the built-in URLValidator is used, it is possible to prepare a special URL which will be used to overload server process when performing validation of the URL.

When using a Spring AOP functionality to secure Struts actions it is possible to perform a DoS attack. Solution is to upgrade to Apache Struts version 2.5.12 or 2.3.33.

If an application allows enter an URL in a form field and built-in URLValidator is used, it is possible to prepare a special URL which will be used to overload server process when performing validation of the URL. Solution is to upgrade to Apache Struts version 2.5.12.

The Jakarta Multipart parser in Apache Struts 2 2.3.x before 2.3.32 and 2.5.x before 2.5.10.1 has incorrect exception handling and error-message generation during file-upload attempts, which allows remote attackers to execute arbitrary commands via a crafted Content-Type, Content-Disposition, or Content-Length HTTP header, as exploited in the wild in March 2017 with a Content-Type header containing a #cmd= string.

Apache Struts 2 before 2.3.29 and 2.5.x before 2.5.1 allow attackers to have unspecified impact via vectors related to improper action name clean up.

The URLValidator class in Apache Struts 2 2.3.20 through 2.3.28.1 and 2.5.x before 2.5.1 allows remote attackers to cause a denial of service via a null value for a URL field.

Apache Tiles 2.1 before 2.1.2, as used in Apache Struts and other products, evaluates Expression Language (EL) expressions twice in certain circumstances, which allows remote attackers to conduct cross-site scripting (XSS) attacks or obtain sensitive information via unspecified vectors, related to the (1) tiles:putAttribute and (2) tiles:insertTemplate JSP tags.