Know every vulnerabilitybefore it knows you.
DevGuard continuously monitors your dependencies and alerts you when CVEs like this one affect your stack — with real-time threat intelligence built for developers.
GHSA-36p3-wjmg-h94x
No affected components available
Spring Framework prior to versions 5.2.20 and 5.3.18 contains a remote code execution vulnerability known as Spring4Shell.
Impact
A Spring MVC or Spring WebFlux application running on JDK 9+ may be vulnerable to remote code execution (RCE) via data binding. The specific exploit requires the application to run on Tomcat as a WAR deployment. If the application is deployed as a Spring Boot executable jar, i.e. the default, it is not vulnerable to the exploit. However, the nature of the vulnerability is more general, and there may be other ways to exploit it.
These are the prerequisites for the exploit:
- JDK 9 or higher
- Apache Tomcat as the Servlet container
- Packaged as WAR
spring-webmvcorspring-webfluxdependency
Patches
Workarounds
For those who are unable to upgrade, leaked reports recommend setting disallowedFields on WebDataBinder through an @ControllerAdvice. This works generally, but as a centrally applied workaround fix, may leave some loopholes, in particular if a controller sets disallowedFields locally through its own @InitBinder method, which overrides the global setting.
To apply the workaround in a more fail-safe way, applications could extend RequestMappingHandlerAdapter to update the WebDataBinder at the end after all other initialization. In order to do that, a Spring Boot application can declare a WebMvcRegistrations bean (Spring MVC) or a WebFluxRegistrations bean (Spring WebFlux).
The vulnerability can be exploited over the network without needing physical access. It is easy for an attacker to exploit this vulnerability. An attacker does not need any special privileges or access rights. No user interaction is needed for the attacker to exploit this vulnerability. The impact is confined to the system where the vulnerability exists. There is a high impact on the confidentiality of the information. There is a high impact on the integrity of the data. There is a high impact on the availability of the system.
Active exploitation in the wild has been confirmed. Immediate patching or mitigation is required.
The exploit probability is critical. The vulnerability is very likely to be exploited in the next 30 days.
We did not find any exploit available. Neither in GitHub repositories nor in the Exploit-Database.
Browse More
Continuously monitor your dependencies and get alerted when vulnerabilities like this one affect your stack.
Checkout DevGuard