I am not sure whether its a basic question...but I am struggling with this issue for a few days. I have created a rule with the following condition.
condition:
is_php and filesize < 1024 and $str1 and ($str2 or $str3 or $str4)
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Ideally, I want to scan the files only under 1KB. But it is triggering for files which is bigger than 1KB. For example.
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[root@server1 ~]# stat -c '%n %s' /home/gal2.php
/home/gal2.php 3693
[root@server1 ~]# clamscan -d me.yara /home/gal2.php
/home/gal2.php: YARA.My_Test_Rule.UNOFFICIAL FOUND
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So as you can see the file is 3K+ in size but still triggering the rule. If I reduce the filesize to 600 it will work fine. What can be the cause? But when I try using direct YARA command this issue is not happening.
Any help will be appreciated...thanks in advance.
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