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Modsecurity-“主机头是数字IP地址”错误的重定向循环

mod-security2 owasp

1

dangel · 技术社区 · 8 年前

看起来有一个ModSecurity OWASP规则,当它检测到有人通过IP地址而不是DNS名称访问您的站点时,它不会以4xx错误进行拒绝,而是直接重定向回“主页”。问题是它重定向回IP地址,这会导致同样的错误再次触发,您会得到一个重定向循环。

是否有方法指定对特定规则采取什么操作?

规则如下。我看不到任何重定向选项,甚至没有任何指定特定错误的选项。

SecRule REQUEST_HEADERS:Host "^[\d.:]+$" \
  "msg:'Host header is a numeric IP address',\
   phase:request,\
   rev:'2',\
   ver:'OWASP_CRS/3.0.0',\
   maturity:'9',\
   accuracy:'9',\
   t:none,\
   block,\
   logdata:'%{matched_var}',\
   severity:'WARNING',\
   id:'920350',\
   tag:'application-multi',\
   tag:'language-multi',\
   tag:'platform-multi',\
   tag:'attack-protocol',\
   tag:'OWASP_CRS/PROTOCOL_VIOLATION/IP_HOST',\
   tag:'WASCTC/WASC-21',\
   tag:'OWASP_TOP_10/A7',\
   tag:'PCI/6.5.10',\
   tag:'http://technet.microsoft.com/en-us/magazine/2005.01.hackerbasher.aspx',\
   setvar:'tx.msg=%{rule.msg}',\
   setvar:tx.anomaly_score=+%{tx.warning_anomaly_score},\
   setvar:tx.%{rule.id}-OWASP_CRS/POLICY/IP_HOST-%{matched_var_name}=%{matched_var}"

和错误日志。。。

--46372f1f-A--
[04/Jun/2016:19:10:43 --0500] V1NuA38AAAEAACCaOHwAAAAR xxx.xxx.xxx.xxx 60414 172.31.41.204 80
--46372f1f-B--
GET / HTTP/1.1
Host: 52.24.56.241
Connection: keep-alive
Cache-Control: max-age=0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8
Upgrade-Insecure-Requests: 1
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/50.0.2661.102 Safari/537.36
Accept-Encoding: gzip, deflate, sdch
Accept-Language: en-US,en;q=0.8

--46372f1f-F--
HTTP/1.1 302 Found
Location: http://52.24.56.241/
Content-Length: 204
Keep-Alive: timeout=5, max=80
Connection: Keep-Alive
Content-Type: text/html; charset=iso-8859-1

--46372f1f-E--
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<html><head>iT LOO
<title>302 Found</title>
</head><body>
<h1>Found</h1>
<p>The document has moved <a href="http://52.24.56.241/">here</a>.</p>
</body></html>

--46372f1f-H--
Message: Access denied with redirection to http://52.24.56.241/ using status 302 (phase 2). Pattern match "^[\\d.:]+$" at REQUEST_HEADERS:Host. [file "/etc/modsecurity/activated_rules/REQUEST-20-PROTOCOL-ENFORCEMENT.conf"] [line "840"] [id "920350"] [rev "2"] [msg "Host header is a numeric IP address"] [data "52.24.56.241"] [severity "WARNING"] [ver "OWASP_CRS/3.0.0"] [maturity "9"] [accuracy "9"] [tag "Host: 52.24.56.241"] [tag "application-multi"] [tag "language-multi"] [tag "platform-multi"] [tag "attack-protocol"] [tag "OWASP_CRS/PROTOCOL_VIOLATION/IP_HOST"] [tag "WASCTC/WASC-21"] [tag "OWASP_TOP_10/A7"] [tag "PCI/6.5.10"] [tag "http://technet.microsoft.com/en-us/magazine/2005.01.hackerbasher.aspx"]
Apache-Error: [file "apache2_util.c"] [line 271] [level 3] [client %s] ModSecurity: %s%s [uri "%s"]%s
Action: Intercepted (phase 2)
Stopwatch: 1465085443076841 1107 (- - -)
Stopwatch2: 1465085443076841 1107; combined=684, p1=288, p2=198, p3=0, p4=0, p5=153, sr=69, sw=45, l=0, gc=0
Response-Body-Transformed: Dechunked
Producer: ModSecurity for Apache/2.9.1 (http://www.modsecurity.org/); OWASP_CRS/3.0.0.
Server: Apache
Engine-Mode: "ENABLED"

ModSecurity如何决定采取哪种操作?
如何告诉ModSecurity停止此错误的重定向循环?

1 回复 | 直到 8 年前

1

dangel 8 年前

如果出现拒绝或“阻止”规则,ModSecurity将查找 SecDefaultAction 中的指令 modsecurity_crs_10_setup.conf 文件对于OWASP_CRS 3.0.0-rc1,此指令从

SecDefaultAction "phase:1,deny,log"
SecDefaultAction "phase:2,deny,log"

到

SecDefaultAction "phase:1,log,redirect:'http://%{request_headers.host}/',tag:'Host: %{request_headers.host}'"
SecDefaultAction "phase:2,log,redirect:'http://%{request_headers.host}/',tag:'Host: %{request_headers.host}'"

这就是导致重定向的原因,规则说阻塞,所以它查找默认操作,默认操作是重定向到主机…在这种情况下,这只是已经指定的IP…还有重定向循环。。。

请注意,此规则将在Apache有机会提供适当的虚拟主机以响应此请求之前触发。

要覆盖此规则(对于3.0.0-rc1),需要修改 RESPONSE-99-EXCEPTIONS.conf 文件并沿..行添加内容。。

SecRuleUpdateActionById 920350 "deny,status:403"

这将拒绝该请求。或者如果你愿意允许。。

SecRuleUpdateActionById 920350 "pass"