dom4j before 2.0.3 and 2.1.x before 2.1.3 allows external DTDs and External Entities by default, which might enable XXE attacks. However, there is popular external documentation from OWASP showing how to enable the safe, non-default behavior in any application that uses dom4j.

Improper validation of certificate with host mismatch in Apache Log4j SMTP appender. This could allow an SMTPS connection to be intercepted by a man-in-the-middle attack which could leak any log messages sent through that appender. Fixed in Apache Log4j 2.12.3 and 2.13.1

A vulnerability was found in Hibernate-Validator. The SafeHtml validator annotation fails to properly sanitize payloads consisting of potentially malicious code in HTML comments and instructions. This vulnerability can result in an XSS attack.

In Apache Commons Beanutils 1.9.2, a special BeanIntrospector class was added which allows suppressing the ability for an attacker to access the classloader via the class property available on all Java objects. We, however were not using this by default characteristic of the PropertyUtilsBean.

It was found that xstream API version 1.4.10 before 1.4.11 introduced a regression for a previous deserialization flaw. If the security framework has not been initialized, it may allow a remote attacker to run arbitrary shell commands when unmarshalling XML or any supported format. e.g. JSON. (regression of CVE-2013-7285)

dom4j version prior to version 2.1.1 contains a CWE-91: XML Injection vulnerability in Class: Element. Methods: addElement, addAttribute that can result in an attacker tampering with XML documents through XML injection. This attack appear to be exploitable via an attacker specifying attributes or elements in the XML document. This vulnerability appears to have been fixed in 2.1.1 or later.

org.slf4j.ext.EventData in the slf4j-ext module in QOS.CH SLF4J before 1.8.0-beta2 allows remote attackers to bypass intended access restrictions via crafted data. EventData in the slf4j-ext module in QOS.CH SLF4J, has been fixed in SLF4J versions 1.7.26 later and in the 2.0.x series.