[5943] in bugtraq
Re: hole in sudo for MP-RAS.
daemon@ATHENA.MIT.EDU (Cy Schubert - ITSD Open Systems Gr)
Mon Jan 12 22:54:26 1998
Date: Mon, 12 Jan 1998 18:54:13 -0800
Reply-To: Cy Schubert - ITSD Open Systems Group <cschuber@uumail.gov.bc.ca>
From: Cy Schubert - ITSD Open Systems Group <cschuber@UUMAIL.GOV.BC.CA>
X-To: "Todd C. Miller" <Todd.Miller@courtesan.com>
To: BUGTRAQ@NETSPACE.ORG
In-Reply-To: Your message of "Mon, 12 Jan 1998 16:28:01 MST."
<199801122328.QAA16120@xerxes.courtesan.com>
> As this seems to only affect that one OS, I'm not sure I would call
> it a bug in sudo. When this was reported for 1.5.2 I took a look
> but couldn't find any way to reproduce it (and I don't have access
> to the OS in question).
I've been able to reproduce the exploit using cu-sudo 1.5.3 under DEC UNIX
4.0B and FreeBSD 2.2.5. After looking at the code the bug can be exploited on
any platform.
Here is a patch to fix the problem, assuming your operating system of choice
supports realpath(3). *BSD, Linux, Solaris, SunOS, DEC UNIX, AIX, and DG/UX
should have no problem with this patch.
diff -ur sudo.v1.5.3.orig/find_path.c sudo.v1.5.3/find_path.c
--- sudo.v1.5.3.orig/find_path.c Wed Nov 13 18:37:22 1996
+++ sudo.v1.5.3/find_path.c Mon Jan 12 17:55:43 1998
@@ -118,7 +118,11 @@
* the error is "not found" -- this way we get the correct error.
*/
if (strchr(file, '/')) {
- (void) strcpy(command, file);
+ if (realpath(file, command) == NULL) {
+ (void) fprintf(stderr, "%s: %s", Argv[0], file);
+ perror("");
+ exit(1);
+ }
if (sudo_goodpath(command)) {
return(command);
} else {
>
> - todd
>
Regards, Phone: (250)387-8437
Cy Schubert Fax: (250)387-5766
UNIX Support OV/VM: BCSC02(CSCHUBER)
ITSD BITNET: CSCHUBER@BCSC02.BITNET
Government of BC Internet: cschuber@uumail.gov.bc.ca
Cy.Schubert@gems8.gov.bc.ca
"Quit spooling around, JES do it."
