mirror of
https://github.com/carlospolop/hacktricks
synced 2024-11-15 01:17:36 +00:00
328 lines
21 KiB
Markdown
328 lines
21 KiB
Markdown
|
||
|
||
<details>
|
||
|
||
<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 to the **latest version of the PEASS or download HackTricks in PDF**? Check the [**SUBSCRIPTION PLANS**](https://github.com/sponsors/carlospolop)!
|
||
|
||
- Discover [**The PEASS Family**](https://opensea.io/collection/the-peass-family), our collection of exclusive [**NFTs**](https://opensea.io/collection/the-peass-family)
|
||
|
||
- Get the [**official PEASS & HackTricks swag**](https://peass.creator-spring.com)
|
||
|
||
- **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)**.**
|
||
|
||
- **Share your hacking tricks by submitting PRs to the** [**hacktricks github repo**](https://github.com/carlospolop/hacktricks)**.**
|
||
|
||
</details>
|
||
|
||
|
||
# Static Analysis
|
||
|
||
## otool
|
||
|
||
```bash
|
||
otool -L /bin/ls #List dynamically linked libraries
|
||
otool -tv /bin/ps #Decompile application
|
||
```
|
||
|
||
## SuspiciousPackage
|
||
|
||
[**SuspiciousPackage**](https://mothersruin.com/software/SuspiciousPackage/get.html) is a tool useful to inspect **.pkg** files (installers) and see what is inside before installing it.\
|
||
These installers have `preinstall` and `postinstall` bash scripts that malware authors usually abuse to **persist** **the** **malware**.
|
||
|
||
## hdiutil
|
||
|
||
This tool allows to **mount** Apple disk images (**.dmg**) files to inspect them before running anything:
|
||
|
||
```bash
|
||
hdiutil attach ~/Downloads/Firefox\ 58.0.2.dmg
|
||
```
|
||
|
||
It will be mounted in `/Volumes`
|
||
|
||
## Objective-C
|
||
|
||
When a function is called in a binary that uses objective-C, the compiled code instead of calling that function, it will call **`objc_msgSend`**. Which will be calling the final function:
|
||
|
||
![](<../../.gitbook/assets/image (560).png>)
|
||
|
||
The params this function expects are:
|
||
|
||
* The first parameter (**self**) is "a pointer that points to the **instance of the class that is to receive the message**". Or more simply put, it’s the object that the method is being invoked upon. If the method is a class method, this will be an instance of the class object (as a whole), whereas for an instance method, self will point to an instantiated instance of the class as an object.
|
||
* The second parameter, (**op**), is "the selector of the method that handles the message". Again, more simply put, this is just the **name of the method.**
|
||
* The remaining parameters are any **values that are required by the method** (op).
|
||
|
||
| **Argument** | **Register** | **(for) objc\_msgSend** |
|
||
| ----------------- | --------------------------------------------------------------- | ------------------------------------------------------ |
|
||
| **1st argument** | **rdi** | **self: object that the method is being invoked upon** |
|
||
| **2nd argument** | **rsi** | **op: name of the method** |
|
||
| **3rd argument** | **rdx** | **1st argument to the method** |
|
||
| **4th argument** | **rcx** | **2nd argument to the method** |
|
||
| **5th argument** | **r8** | **3rd argument to the method** |
|
||
| **6th argument** | **r9** | **4th argument to the method** |
|
||
| **7th+ argument** | <p><strong>rsp+</strong><br><strong>(on the stack)</strong></p> | **5th+ argument to the method** |
|
||
|
||
## Packed binaries
|
||
|
||
* Check for high entropy
|
||
* Check the strings (is there is almost no understandable string, packed)
|
||
* The UPX packer for MacOS generates a section called "\_\_XHDR"
|
||
|
||
# Dynamic Analysis
|
||
|
||
{% hint style="warning" %}
|
||
Note that in order to debug binaries, **SIP needs to be disabled** (`csrutil disable` or `csrutil enable --without debug`) or to copy the binaries to a temporary folder and **remove the signature** with `codesign --remove-signature <binary-path>` or allow the debugging of the binary (you can use [this script](https://gist.github.com/carlospolop/a66b8d72bb8f43913c4b5ae45672578b))
|
||
{% endhint %}
|
||
|
||
{% hint style="warning" %}
|
||
Note that in order to **instrument system binarie**s, (such as `cloudconfigurationd`) on macOS, **SIP must be disabled** (just removing the signature won't work).
|
||
{% endhint %}
|
||
|
||
## dtruss
|
||
|
||
```bash
|
||
dtruss -c ls #Get syscalls of ls
|
||
dtruss -c -p 1000 #get syscalls of PID 1000
|
||
```
|
||
|
||
## ktrace
|
||
|
||
You can use this one even with **SIP activated**
|
||
|
||
```bash
|
||
ktrace trace -s -S -t c -c ls | grep "ls("
|
||
```
|
||
|
||
## dtrace
|
||
|
||
It allows users access to applications at an extremely **low level** and provides a way for users to **trace** **programs** and even change their execution flow. Dtrace uses **probes** which are **placed throughout the kernel** and are at locations such as the beginning and end of system calls.
|
||
|
||
The available probes of dtrace can be obtained with:
|
||
|
||
```bash
|
||
dtrace -l | head
|
||
ID PROVIDER MODULE FUNCTION NAME
|
||
1 dtrace BEGIN
|
||
2 dtrace END
|
||
3 dtrace ERROR
|
||
43 profile profile-97
|
||
44 profile profile-199
|
||
```
|
||
|
||
The probe name consists of four parts: the provider, module, function, and name (`fbt:mach_kernel:ptrace:entry`). If you not specifies some part of the name, Dtrace will apply that part as a wildcard.
|
||
|
||
A more detailed explanation and more examples can be found in [https://illumos.org/books/dtrace/chp-intro.html](https://illumos.org/books/dtrace/chp-intro.html)
|
||
|
||
### Examples
|
||
|
||
* In line
|
||
|
||
```bash
|
||
#Count the number of syscalls of each running process
|
||
sudo dtrace -n 'syscall:::entry {@[execname] = count()}'
|
||
```
|
||
|
||
* script
|
||
|
||
```bash
|
||
syscall:::entry
|
||
/pid == $1/
|
||
{
|
||
}
|
||
|
||
#Log every syscall of a PID
|
||
sudo dtrace -s script.d 1234
|
||
```
|
||
|
||
```bash
|
||
syscall::open:entry
|
||
{
|
||
printf("%s(%s)", probefunc, copyinstr(arg0));
|
||
}
|
||
syscall::close:entry
|
||
{
|
||
printf("%s(%d)\n", probefunc, arg0);
|
||
}
|
||
|
||
#Log files opened and closed by a process
|
||
sudo dtrace -s b.d -c "cat /etc/hosts"
|
||
```
|
||
|
||
```bash
|
||
syscall:::entry
|
||
{
|
||
;
|
||
}
|
||
syscall:::return
|
||
{
|
||
printf("=%d\n", arg1);
|
||
}
|
||
|
||
#Log sys calls with values
|
||
sudo dtrace -s syscalls_info.d -c "cat /etc/hosts"
|
||
```
|
||
|
||
## ProcessMonitor
|
||
|
||
[**ProcessMonitor**](https://objective-see.com/products/utilities.html#ProcessMonitor) is a very useful tool to check the process related actions a process is performing (for example, monitor which new processes a process is creating).
|
||
|
||
## FileMonitor
|
||
|
||
[**FileMonitor**](https://objective-see.com/products/utilities.html#FileMonitor) allows to monitor file events (such as creation, modifications, and deletions) providing detailed information about such events.
|
||
|
||
## fs\_usage
|
||
|
||
Allows to follow actions performed by processes:
|
||
|
||
```bash
|
||
fs_usage -w -f filesys ls #This tracks filesystem actions of proccess names containing ls
|
||
fs_usage -w -f network curl #This tracks network actions
|
||
```
|
||
|
||
## TaskExplorer
|
||
|
||
[**Taskexplorer**](https://objective-see.com/products/taskexplorer.html) is useful to see the **libraries** used by a binary, the **files** it's using and the **network** connections.\
|
||
It also checks the binary processes against **virustotal** and show information about the binary.
|
||
|
||
## lldb
|
||
|
||
**lldb** is the de **facto tool** for **macOS** binary **debugging**.
|
||
|
||
```bash
|
||
lldb ./malware.bin
|
||
lldb -p 1122
|
||
lldb -n malware.bin
|
||
lldb -n malware.bin --waitfor
|
||
```
|
||
|
||
| **(lldb) Command** | **Description** |
|
||
| ----------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
|
||
| **run (r)** | Starting execution, which will continue unabated until a breakpoint is hit or the process terminates. |
|
||
| **continue (c)** | Continue execution of the debugged process. |
|
||
| **nexti (n)** | Execute the next instruction. This command will skip over function calls. |
|
||
| **stepi (s)** | Execute the next instruction. Unlike the nexti command, this command will step into function calls. |
|
||
| **finish (f)** | Execute the rest of the instructions in the current function (“frame”) return and halt. |
|
||
| **control + c** | Pause execution. If the process has been run (r) or continued (c), this will cause the process to halt ...wherever it is currently executing. |
|
||
| **breakpoint (b)** | <p>b main</p><p>b -[NSDictionary objectForKey:]</p><p>b 0x0000000100004bd9</p><p>br l #Breakpoint list</p><p>br e/dis <num> #Enable/Disable breakpoint</p><p>breakpoint delete <num></p> |
|
||
| **help** | <p>help breakpoint #Get help of breakpoint command</p><p>help memory write #Get help to write into the memory</p> |
|
||
| **reg** | <p>reg read $rax</p><p>reg write $rip 0x100035cc0</p> |
|
||
| **x/s \<reg/memory address>** | Display the memory as a null-terminated string. |
|
||
| **x/i \<reg/memory address>** | Display the memory as assembly instruction. |
|
||
| **x/b \<reg/memory address>** | Display the memory as byte. |
|
||
| **print object (po)** | <p>This will print the object referenced by the param</p><p>po $raw</p><p><code>{</code></p><p> <code>dnsChanger = {</code></p><p> <code>"affiliate" = "";</code></p><p> <code>"blacklist_dns" = ();</code></p><p>Note that most of Apple’s Objective-C APIs or methods return objects, and thus should be displayed via the “print object” (po) command. If po doesn't produce a meaningful output use <code>x/b</code><br></p> |
|
||
| **memory write** | memory write 0x100600000 -s 4 0x41414141 #Write AAAA in that address |
|
||
|
||
{% hint style="info" %}
|
||
When calling the **`objc_sendMsg`** function, the **rsi** register holds the **name of the method** as a null-terminated (“C”) string. To print the name via lldb do:
|
||
|
||
`(lldb) x/s $rsi: 0x1000f1576: "startMiningWithPort:password:coreCount:slowMemory:currency:"`
|
||
|
||
`(lldb) print (char*)$rsi:`\
|
||
`(char *) $1 = 0x00000001000f1576 "startMiningWithPort:password:coreCount:slowMemory:currency:"`
|
||
|
||
`(lldb) reg read $rsi: rsi = 0x00000001000f1576 "startMiningWithPort:password:coreCount:slowMemory:currency:"`
|
||
{% endhint %}
|
||
|
||
## Anti-Dynamic Analysis
|
||
|
||
### VM detection
|
||
|
||
* The command **`sysctl hw.model`** returns "Mac" when the **host is a MacOS** but something different when it's a VM.
|
||
* Playing with the values of **`hw.logicalcpu`** and **`hw.physicalcpu`** some malwares try to detect if it's a VM.
|
||
* Some malwares can also **detect** if the machine is **VMware** based on the MAC address (00:50:56).
|
||
* It's also possible to find **if a process is being debugged** with a simple code such us:
|
||
* `if(P_TRACED == (info.kp_proc.p_flag & P_TRACED)){ //process being debugged }`
|
||
* It can also invoke the **`ptrace`** system call with the **`PT_DENY_ATTACH`** flag. This **prevents** a deb**u**gger from attaching and tracing.
|
||
* You can check if the **`sysctl` ** or**`ptrace`** function is being **imported** (but the malware could import it dynamically)
|
||
* As noted in this writeup, “[Defeating Anti-Debug Techniques: macOS ptrace variants](https://alexomara.com/blog/defeating-anti-debug-techniques-macos-ptrace-variants/)” :\
|
||
“_The message Process # exited with **status = 45 (0x0000002d)** is usually a tell-tale sign that the debug target is using **PT\_DENY\_ATTACH**_”
|
||
|
||
# Fuzzing
|
||
|
||
## [ReportCrash](https://ss64.com/osx/reportcrash.html#:\~:text=ReportCrash%20analyzes%20crashing%20processes%20and%20saves%20a%20crash%20report%20to%20disk.\&text=ReportCrash%20also%20records%20the%20identity,when%20a%20crash%20is%20detected.)
|
||
|
||
ReportCrash **analyzes crashing processes and saves a crash report to disk**. A crash report contains information that can **help a developer diagnose** the cause of a crash.\
|
||
For applications and other processes **running in the per-user launchd context**, ReportCrash runs as a LaunchAgent and saves crash reports in the user's `~/Library/Logs/DiagnosticReports/`\
|
||
For daemons, other processes **running in the system launchd context** and other privileged processes, ReportCrash runs as a LaunchDaemon and saves crash reports in the system's `/Library/Logs/DiagnosticReports`
|
||
|
||
If you are worried about crash reports **being sent to Apple** you can disable them. If not, crash reports can be useful to **figure out how a server crashed**.
|
||
|
||
```bash
|
||
#To disable crash reporting:
|
||
launchctl unload -w /System/Library/LaunchAgents/com.apple.ReportCrash.plist
|
||
sudo launchctl unload -w /System/Library/LaunchDaemons/com.apple.ReportCrash.Root.plist
|
||
|
||
#To re-enable crash reporting:
|
||
launchctl load -w /System/Library/LaunchAgents/com.apple.ReportCrash.plist
|
||
sudo launchctl load -w /System/Library/LaunchDaemons/com.apple.ReportCrash.Root.plist
|
||
```
|
||
|
||
## Sleep
|
||
|
||
While fuzzing in a MacOS it's important to not allow the Mac to sleep:
|
||
|
||
* systemsetup -setsleep Never
|
||
* pmset, System Preferences
|
||
* [KeepingYouAwake](https://github.com/newmarcel/KeepingYouAwake)
|
||
|
||
### SSH Disconnect
|
||
|
||
If you are fuzzing via a SSH connection it's important to make sure the session isn't going to day. So change the sshd\_config file with:
|
||
|
||
* TCPKeepAlive Yes
|
||
* ClientAliveInterval 0
|
||
* ClientAliveCountMax 0
|
||
|
||
```bash
|
||
sudo launchctl unload /System/Library/LaunchDaemons/ssh.plist
|
||
sudo launchctl load -w /System/Library/LaunchDaemons/ssh.plist
|
||
```
|
||
|
||
## Internal Handlers
|
||
|
||
[**Checkout this section**](./#file-extensions-apps) to find out how you can find which app is responsible of **handling the specified scheme or protocol**.
|
||
|
||
## Enumerating Network Processes
|
||
|
||
This interesting to find processes that are managing network data:
|
||
|
||
```bash
|
||
dtrace -n 'syscall::recv*:entry { printf("-> %s (pid=%d)", execname, pid); }' >> recv.log
|
||
#wait some time
|
||
sort -u recv.log > procs.txt
|
||
cat procs.txt
|
||
```
|
||
|
||
Or use `netstat` or `lsof`
|
||
|
||
## More Fuzzing MacOS Info
|
||
|
||
* [https://github.com/bnagy/slides/blob/master/OSXScale.pdf](https://github.com/bnagy/slides/blob/master/OSXScale.pdf)
|
||
* [https://github.com/bnagy/francis/tree/master/exploitaben](https://github.com/bnagy/francis/tree/master/exploitaben)
|
||
* [https://github.com/ant4g0nist/crashwrangler](https://github.com/ant4g0nist/crashwrangler)
|
||
|
||
# References
|
||
|
||
* [**OS X Incident Response: Scripting and Analysis**](https://www.amazon.com/OS-Incident-Response-Scripting-Analysis-ebook/dp/B01FHOHHVS)
|
||
* [**https://www.youtube.com/watch?v=T5xfL9tEg44**](https://www.youtube.com/watch?v=T5xfL9tEg44)
|
||
* [**https://taomm.org/vol1/analysis.html**](https://taomm.org/vol1/analysis.html)
|
||
|
||
|
||
<details>
|
||
|
||
<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 to the **latest version of the PEASS or download HackTricks in PDF**? Check the [**SUBSCRIPTION PLANS**](https://github.com/sponsors/carlospolop)!
|
||
|
||
- Discover [**The PEASS Family**](https://opensea.io/collection/the-peass-family), our collection of exclusive [**NFTs**](https://opensea.io/collection/the-peass-family)
|
||
|
||
- Get the [**official PEASS & HackTricks swag**](https://peass.creator-spring.com)
|
||
|
||
- **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)**.**
|
||
|
||
- **Share your hacking tricks by submitting PRs to the** [**hacktricks github repo**](https://github.com/carlospolop/hacktricks)**.**
|
||
|
||
</details>
|
||
|
||
|