Leaving No Safe Haven For Commandline Obfuscation (The Second Part)

In part one of these blog entries on command line obfuscation in Windows ( which you can find here , if you haven't read it), we covered some real basic SPL for detecting the usage of double quotes to potentially circumvent SIEM detections. One of the things I forgot to mention then is that counting specific characters in fields has a lot of potential uses within Splunk searches if you are prepared to think outside the box a little. For instance let's say you were looking at Apache web logs and you were wanting to find instances of directory (or path) traversal, someone appending something like "../../../../../../../../../../../../etc/passwd%00" to a url to try to get at your valuable files, you could modify the SPL as follows: index=apache sourcetype=access_combined | eval traversalCount=mvcount(split( uri,"."))-1 | where traversalCount >=4 | stats values(uri) BY traversalCount clientip status This would give you any instances of uris containing...