LDAP Injection not being caught by the one rule about owasp-modsecurity-crs HOT 7 CLOSED

I ran your test multipart payload through my own CRS install and the debug log showed this -

#####################################
T (0) htmlEntityDecode: ")(objectClass%3D_"
T (0) lowercase: ")(objectclass%3d_"
Transformation completed in 69 usec.
Executing operator "rx" with param "(?:((?:\W_?(?:objectc(?:ategory|lass)|homedirectory|[gu]idnumber|cn)\b\W_?=|[^\w\x80-\xFF]?[!&|][^\w\x80-\xFF]?()|)[^\w\x80-\xFF]?([^\w\x80-\xFF]?[!&|])" against ARGS:.cgifields.
Target value: ")(objectclass%3d*"
Operator completed in 2 usec.
Rule returned 0.
#####################################

I believe the issue is that the %3d data is not being decoded to "=" as it is by default when it is when in a query_string. I would suggest you modify the rule to add in the t:urlDecodeUni tfns action and retest.

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Ryan, thanks for your incredible responsiveness. I implemented the rule with the addition of t:urlDecodeUni in the custom rule set and reran the LDAP Injection attacks.

That one change stopped every attack dead in its tracks except this one (some vals obfuscated):

GET /application/?)(objectClass= HTTP/1.1
2 Host: hostname.utdallas.edu
3 User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9) Gecko/20080630 Firefox/3.0
4 Accept: text/html,application/xhtml+xml,application/xml;q=0.9,/;q=0.8
5 Accept-Language: en-us,en;q=0.5
6 Accept-Encoding:
7 Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
8 Keep-Alive: 15
9 Connection: keep-alive
10 X-Cenzic-Spider-Send-HeadRequest: true
11 Referer: https://hostname.utdallas.edu/application/A-CS3341-FALL2013/

An incredible yield from one simple change.

from owasp-modsecurity-crs.

I will test soon but this should be caught in the ARGS_NAMES collection.

from owasp-modsecurity-crs.

In looking at the debug log - this payload does not match as the regex is looking for a trailing "=" however when ModSecurity is parsing the query string value, it breaks up the data using "=" as the separator for ARGS_NAMES and ARGS values.

What you could do would be to add QUERY_STRING to the SecRule variable list.

from owasp-modsecurity-crs.

Did checking QUERY_STRING work for you?

from owasp-modsecurity-crs.

I haven't tried that yet, but I'll do it now. I got sidetracked with other issues.

from owasp-modsecurity-crs.

This is long overdue. If this is still a problem please reopen it.

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