CVE-2017-4995: Critical severity spring security vulnerability
An issue was discovered in Pivotal Spring Security 4.2.0.RELEASE through 4.2.2.RELEASE, and Spring Security 5.0.0.M1. When configured to enable default typing, Jackson contained a deserialization vulnerability that could lead to arbitrary code execution. Jackson fixed this vulnerability by blacklisting known "deserialization gadgets." Spring Security configures Jackson with global default typing enabled, which means that (through the previous exploit) arbitrary code could be executed if all of the following is true: (1) Spring Security's Jackson support is being leveraged by invoking SecurityJackson2Modules.getModules(ClassLoader) or SecurityJackson2Modules.enableDefaultTyping(ObjectMapper); (2) Jackson is used to deserialize data that is not trusted (Spring Security does not perform deserialization using Jackson, so this is an explicit choice of the user); and (3) there is an unknown (Jackson is not blacklisting it already) "deserialization gadget" that allows code execution present on the classpath. Jackson provides a blacklisting approach to protecting against this type of attack, but Spring Security should be proactive against blocking unknown "deserialization gadgets" when Spring Security enables default typing.
Other sources
Pivotal Spring Security could allow a remote attacker to execute arbitrary code on the system, caused by a deserialization flaw in the default Jackson configuration. By sending a specially-crafted request, an attacker could exploit this vulnerability to execute arbitrary code on the system.
Affected Software
Event History
Frequently Asked Questions
What is CVE-2017-4995?
CVE-2017-4995 is a vulnerability in Pivotal Spring Security and Spring Security that allows a remote attacker to execute arbitrary code on the system.
How does the CVE-2017-4995 vulnerability occur?
The CVE-2017-4995 vulnerability occurs due to a deserialization vulnerability in Jackson when configured to enable default typing.
What is the severity rating of CVE-2017-4995?
CVE-2017-4995 has a severity rating of 9.8 (Critical).
Which software versions are affected by CVE-2017-4995?
Pivotal Spring Security versions 4.2.0.RELEASE through 4.2.2.RELEASE and Spring Security version 5.0.0.M1 are affected by CVE-2017-4995.
How can I fix the CVE-2017-4995 vulnerability?
To fix the CVE-2017-4995 vulnerability, update Pivotal Spring Security to version 4.2.3.RELEASE or later, or update Spring Security to version 5.0.0.M2 or later.