COMMAND
Netscape Directory Server
SYSTEMS AFFECTED
- Netscape Directory Server 4.1 (bundled with Netscape Messaging Server)
- Netscape Directory Server 4.12 (may be DoS only)
PROBLEM
Following is based on a @stake Advisory Notification (A030701-1)
by Frank Swiderski. The Netscape Directory Server that comes with
Netscape Messaging Server 4.15SP3 is vulnerable to a buffer
overflow condition if a specially crafted query is received. The
Directory Server is used to store various user information for
Messenger. The overflow can result in either a denial of service
or arbitrary code execution on the server. Netscape Directory
Server 4.12 is also subject to the same overflow, however, code
execution may or may not be possible due to the location the
resultant string is copied to.
Note that Netscape Messanging Service will ask for a directory
server to use during installation; by default it will install and
use its own copy of Directory Server 4.1. The Messanging service
also enables services which use the Directory Server, such as
SMTPD, by default. Both the Messanging Server and the Directory
server are available for many flavors of Unix as well as for
Windows NT, and are commonly used for managing corporate email.
For more information on LDAP and its protocols, ldapman.org has an
excellent collection of LDAP RFC links at
http://ldapman.org/ldap_rfcs.html
For SMTP, see RFC-821 and RFC-822.
The exposure to existing customers is isolated to the Directory
Server 4.11 and 4.12 products. As reported, the overflow can
result in either a denial of service or arbitrary code execution
on the server. Netscape Directory Server 4.12 is also subject to
the same denial of service overflow, however, code execution is
not possible.
The Netscape Mail Server 4.15p3 issue of a buffer overflow in the
SMTP session has been resolved in a fix in the NMS 4.15p4 release.
This fix limits the line size of any given command in SMTP command
mode. Should you send a very long (> 16KB) line to the MTA in
command mode, you will get a disconnect with a reply of 550 +
text.
The iPlanet Messaging Server 5.0 release bundles Directory Server
4.12, and it also requires the upgrade to Directory Server 4.13.
Messaging Server 5.0 does not contain the same SMTP session
overflow issue.
Original advisory:
http://www.atstake.com/research/advisories/2001/a030701-1.txt
SOLUTION
iPlanet Directory Server (iDS) Support greatly appreciates these
issues being brought to their attention. These issues do occur in
the following iPlanet products:
For all products, an immediate upgrade to Directory Server 4.13 is
available through the iPlanet Support Channel. In addition, NS
recommends NMS 4.15 customers upgrade to Patch 4.