26th Sep 2002 [SBWID-5279]
COMMAND
AOLServer DB Proxy Daemon Format String Vulnerability
SYSTEMS AFFECTED
AOLServer 3.4.2, 3.4.1, 3.4, 3.3.1, 3.2.1, 3.2, 3.1, 3.0
PROBLEM
From Guillaume Pelat of INTEXXIA [http://www.intexxia.com] security
advisory [ID #1052-300102] :
AOL Server provides an API to develop external database driver proxy daemons.
Those daemons are linked to a library (libnspd.a).
The Laboratory intexxia found a format string and a buffer overflow
vulnerability in the 'Ns_PdLog' function of the library. Successful
exploitation of the bug could allow an attacker to execute code and get
access on the system.
As a result, all the External Driver Proxy Daemons using the 'Ns_PdLog'
function with the 'Error' or 'Notice' parameter are potentially
vulnerable.
SOLUTION
This vulnerability has been fixed in the current version in CVS branch
nsd_v3_r3_p0 (post-AOLserver 3.4.2) and can be used for any affected
version. The patch used was created by intexxia and can be found in
attachment. More information can be found at the following URL :
http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/aolserver/aolserver/nspd/log.c.diff?r1=1.4&r2=1.4.6.1
diff -dru aolserver-3.4.2/nspd/log.c aolserver-3.4.2-patched/nspd/log.c
--- aolserver-3.4.2/nspd/log.c Tue Aug 15 22:24:33 2000
+++ aolserver-3.4.2-patched/nspd/log.c Wed Jan 30 09:03:11 2002
@@ -206,14 +206,13 @@
char msgbuf[4096];
=20
va_start(ap, format);
- vsprintf(msgbuf, format, ap);
+ vsnprintf(msgbuf, sizeof (msgbuf), format, ap);
va_end(ap);
- syslog(priority, msgbuf);
+ syslog(priority, "%s", msgbuf);
}
}
}
=20
-=0C
/*
=
*----------------------------------------------------------------------
*