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.
OGNL provides, among other features, extensive expression evaluation capabilities. This vulnerability allows a malicious user to bypass the '#'-usage protection built into the ParametersInterceptor, thus being able to manipulate server side context objects. This behavior was already addressed in S2-003, but it turned out that the resulting fix based on whitelisting acceptable parameter names closed the vulnerability only partially.
Multiple cross-site scripting (XSS) vulnerabilities in XWork in Apache Struts 2.x before 2.2.3, and OpenSymphony XWork in OpenSymphony WebWork, allow remote attackers to inject arbitrary web script or HTML via vectors involving (1) an action name, (2) the action attribute of an s:submit element, or (3) the method attribute of an s:submit element.
Apache Struts 2.0.0 through 2.3.15.1 allows remote attackers to bypass access controls via a crafted action: prefix.
Apache Struts 2.0.0 through 2.3.15.1 enables Dynamic Method Invocation by default, which has unknown impact and attack vectors.
Multiple open redirect vulnerabilities in Apache Struts 2.0.0 through 2.3.15 allow remote attackers to redirect users to arbitrary web sites and conduct phishing attacks via a URL in a parameter using the (1) redirect: or (2) redirectAction: prefix.
Apache Struts 2.0.0 through 2.3.x before 2.3.20 uses predictable <s:token/> values, which allows remote attackers to bypass the CSRF protection mechanism.
Apache Struts 2.x before 2.3.24.1 allows remote attackers to manipulate Struts internals, alter user sessions, or affect container settings via vectors involving a top object.
XSLTResult allows for the location of a stylesheet being passed as a request parameter. In some circumstances this can be used to inject remotely executable code.
Apache Struts 2.0.0 through 2.3.24.1 does not properly cache method references when used with OGNL before 3.0.12, which allows remote attackers to cause a denial of service (block access to a web site) via unspecified vectors.
Apache Struts 2.3.19 to 2.3.20.2, 2.3.21 to 2.3.24.1, and 2.3.25 to 2.3.28, when Dynamic Method Invocation is enabled, allow remote attackers to execute arbitrary code via method: prefix, related to chained expressions.
The TextParseUtil.translateVariables method in Apache Struts 2.x before 2.3.20 allows remote attackers to execute arbitrary code via a crafted OGNL expression with ANTLR tooling.
Apache Struts 2.x before 2.3.25 does not sanitize text in the Locale object constructed by I18NInterceptor, which might allow remote attackers to conduct cross-site scripting (XSS) attacks via unspecified vectors involving language display.