bitterzzzz/cve-2021-43297-pocProof-of-concept exploit for CVE-2021-43297, achieving remote code execution in Apache Dubbo <= 2.7.13 via Hessian-Lite deserialization.
Apache Dubbo Hessian-Lite 3.2.11 and earlier versions contain a potential RCE attack risk. When Hessian-Lite encounters a serialization exception, it outputs related information, which may trigger the toString method of certain maliciously crafted Beans, leading to an RCE attack.
The initial POC could only achieve RCE on Apache Dubbo <= 2.7.8. The principle is described in the 先知 article (will be updated after review approval). After submitting, further research was conducted, and RCE can now be achieved on Apache Dubbo <= 2.7.13. The principle analysis can be found in my blog post
The effect is as follows
POC exploitation conditions:
wget http://archive.apache.org/dist/zookeeper/zookeeper-3.3.3/zookeeper-3.3.3.tar.gz
tar zxvf zookeeper-3.3.3.tar.gz
cd zookeeper-3.3.3
cp conf/zoo_sample.cfg conf/zoo.cfg
vim conf/zoo.cfg
# The number of milliseconds of each tick
tickTime=2000
# The number of ticks that the initial
# synchronization phase can take
initLimit=10
# The number of ticks that can pass between
# sending a request and getting an acknowledgement
syncLimit=5
# the directory where the snapshot is stored.
dataDir=/absolute/path/zookeeper-3.3.3/data
# the port at which the clients will connect
clientPort=2181
mkdir data
touch data/myid
cd /private/var/tmp/zookeeper-3.3.3/bin
./zkServer.sh start
git clone https://github.com/apache/dubbo-samples.git
cd dubbo-samples/dubbo-samples-api
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>org.example</groupId>
<artifactId>dubbomytest</artifactId>
<packaging>pom</packaging>
<version>1.0-SNAPSHOT</version>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<source>8</source>
<target>8</target>
</configuration>
</plugin>
</plugins>
</build>
<properties>
<source.level>1.8</source.level>
<target.level>1.8</target.level>
<dubbo.version>2.7.6</dubbo.version>
<junit.version>4.12</junit.version>
<docker-maven-plugin.version>0.30.0</docker-maven-plugin.version>
<jib-maven-plugin.version>1.2.0</jib-maven-plugin.version>
<maven-compiler-plugin.version>3.7.0</maven-compiler-plugin.version>
<maven-failsafe-plugin.version>2.21.0</maven-failsafe-plugin.version>
<image.name>${project.artifactId}:${dubbo.version}</image.name>
<java-image.name>openjdk:8</java-image.name>
<dubbo.port>20880</dubbo.port>
<zookeeper.port>2181</zookeeper.port>
<main-class>org.apache.dubbo.samples.provider.Application</main-class>
</properties>
<dependencies>
<dependency>
<groupId>org.apache.dubbo</groupId>
<artifactId>dubbo</artifactId>
<version>2.7.3</version>
</dependency>
<dependency>
<groupId>org.apache.dubbo</groupId>
<artifactId>dubbo-common</artifactId>
<version>2.7.3</version>
</dependency>
<dependency>
<groupId>org.apache.dubbo</groupId>
<artifactId>dubbo-dependencies-zookeeper</artifactId>
<version>2.7.3</version>
<type>pom</type>
</dependency>
<dependency>
<groupId>org.apache.xbean</groupId>
<artifactId>xbean-naming</artifactId>
<version>4.15</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>${junit.version}</version>
<scope>test</scope>
</dependency>
</dependencies>
</project>
Both the provider side and the local environment need to install it, with the dependency as follows
<dependency>
<groupId>org.apache.xbean</groupId>
<artifactId>xbean-naming</artifactId>
<version>4.15</version>
</dependency>
Add dubbo-samples-api in IDEA, note that you need to modify the zookeeper and dubbo ports, and also modify the code in Application.java:
service.setRegistry(new RegistryConfig("zookeeper://" + zookeeperHost + ":" + zookeeperPort+"/?timeout=250000"));
This prevents higher versions of dubbo from failing to connect due to slow zookeeper connection establishment
Start Application.java in dubbo-samples-api in IDEA
After startup, the output dubbo service started indicates that dubbo has been started
<dependency>
<groupId>org.apache.dubbo</groupId>
<artifactId>dubbo-common</artifactId>
<version>2.7.3</version>
</dependency>
<dependency>
<groupId>org.apache.dubbo</groupId>
<artifactId>dubbo</artifactId>
<version>2.7.3</version>
</dependency>
<dependency>
<groupId>org.apache.dubbo</groupId>
<artifactId>dubbo-dependencies-zookeeper</artifactId>
<version>2.7.3</version>
<type>pom</type>
</dependency>
<dependency>
<groupId>com.caucho</groupId>
<artifactId>hessian</artifactId>
<version>4.0.51</version>
</dependency>
Compile ExecTest.java, then modify the path of ExecTest.class in HttpServer.java, then execute the HttpServer.main method, and finally execute the HessianLitePoc.main method