Pwntools v3.0 Released via /r/netsec

Hey guys, Pwntools developer here!

If you haven’t used it before, Pwntools is a Python library/framework developing exploits for Capture The Flag (CTF) competitions, like DEFCON CTF, picoCTF, and wargames like pwnable.kr.

Pwntools makes the exploit developer’s life easier by providing a suite of easy and quick tools that do exactly what an exploit developer would want them to — without the hassle of writing template code or dealing with various minor gotchas.

If you’re a new user to pwntools, you can check out the Getting Started page on the documentation, available at docs.pwntools.com.

The v3.0 release is a big one for us, and our first in over eighteen months!

Both existing and new users can install Pwntools with a simple pip install --upgrade pwntools.

For those who just want to see what’s new, you can check out the CHANGELOG.md here.

In particular, all of the changes which were made on the Binjitsu fork of Pwntools have been merged back into upstream Pwntools.

Everything below here is the changelog, for ease of reference.

3.0.0 (August 20 2016)

This was a large release (1305 commits since 2.2.0) with a lot of bugfixes and changes. The Binjitsu project, a fork of Pwntools, was merged back into Pwntools. As such, its features are now available here.

As always, the best source of information on specific features is the comprehensive docs at http://ift.tt/2bralSQ.

This list of changes is non-complete, but covers all of the significant changes which were appropriately documented.

Android

Android support via a new adb module, context.device, context.adb_host, and context.adb_port.

Assembly and Shellcode

• Assembly module enhancements for making ELF modules from assembly or pre-assembled shellcode. See asm.make_elf and asm.make_elf_from_assembly.
• asm and shellcraft command-line tools support flags for the new shellcode encoders
• asm and shellcraft command-line tools support --debug flag for automatically launching GDB on the result
• Added MIPS, PowerPC, and AArch64 support to the shellcraft module
• Added Cyber Grand Challenge (CGC) support to the shellcraft module
• Added syscall wrappers for every Linux syscall for all supported architectures to the shellcraft module
  • e.g. shellcraft.<arch>.gettimeofday
  • (e.g. shellcraft.i386.linux.foobar)
• Added in-memory ELF loaders for most supported architectures
  • Only supports statically-linked binaries
  • shellcraft.<arch>.linux.loader

Context Module

• Added context.aslr which controls ASLR on launched processes. This works with both process() and ssh.process(), and can be specified per-process with the aslr= keyword argument.
• Added context.binary which automatically sets all context variables from an ELF file.
• Added context.device, context.adb, context.adb_port, and context.adb_host for connecting to Android devices.
• Added context.kernel setting for SigReturn-Oriented-Programming (SROP).
• Added context.log_file setting for sending logs to a file. This can be set with the LOG_FILE magic command-line option.
• Added context.noptrace setting for disabling actions which require ptrace support. This is useful for turning all gdb.debug and gdb.attach options into no-ops, and can be set via the NOPTRACE magic command-line option.
• Added context.proxy which hooks all connections and sends them to a SOCKS4/SOCKS5. This can be set via the PROXY magic command-line option.
• Added context.randomize to control randommization of settings like XOR keys and register ordering (default off).
• Added context.termianl for setting how to launch commands in a new terminal.

DynELF and MemLeak Module

• Added a DynELF().libc property which attempt to find the remote libc and download the ELF from LibcDB.
• Added a DynELF().stack property which leaks the __environ pointer from libc, making it easy to leak stack addresses.
• Added MemLeak.String and MemLeak.NoNewlines and other related helpers for handling special leakers which cannot e.g. handle newlines in the leaked addresses and which leak a C string (e.g. auto-append a '\x00').
• Enhancements for leaking speed via MemLeak.compare to avoid leaking an entire field if we can tell from a partial leak that it does not match what we are searching for.

Encoders Module

• Added a pwnlib.encoders module for assembled-shellcode encoders/decoders
• Includes position-indepentent basic XOR encoders
• Includes position-independent delta encoders
• Includes non-position-independent alphanumeric encoders for Intel
• Includes position-independent alphanumeric encoders for ARM/Thumb

ELF Module

• Added a Core object which can parse core-files, in order to extract / search for memory contents, and extract register states (e.g. Core('./corefile').eax).

Format Strings

• Added a basic fmtstr module for assisting with Format String exploitation

GDB Module

• Added support for debugging Android devices when context.os=='android'
• Added helpers for debugging shellcode snippets with gdb.debug_assembly() and gdb.debug_shellcode()

ROP Module

• Added support for SigReturn via pwnlib.rop.srop
  • Occurs automatically when syscalls are invoked and a function cannot be found
  • SigReturn frames can be constructed manually with SigreturnFrame() objects
• Added functional doctests for ROP and SROP

Tubes Process Module

• process() has many new options, check out the documentation
  • aslr controls ASLR
  • setuid can disable the effect of setuid, allowing core dumps (useful for extracting crash state via the new Core() object)
  • TTY echo and control characters can be enabled via raw argument
• stdout and stderr are now PTYs by default
  • stdin can be set to a PTY also via setting stdin=process.PTY

Tubes SSH Module

• Massive enhancements all over
• ssh objects now have a ssh.process() method which avoids the need to handle shell expansion via the old ssh.run() method
• Files are downloaded via SFTP if available
• New download and upload methods auto-detect whether the target is a file or directory and acts accordingly
• Added listen() method alias for listen_remote()
• Added remote() method alias for connect_remote()

Utilities

• Added fit() method to combine the functionality of flat() with the functionality of cyclic()
• Added negative() method to negate the value of an integer via two’s complement, with respect to the current integer size (context.bytes).
• Added xor_key() method to generate an XOR key which avoids undesirable bytes over a given input.
• Added a multi-threaded bruteforce() implementation, mbruteforce().
• Added dealarm_shell() helper to remove the effects of alarm() after you’ve popped a shell.