Home page logo
/

fulldisclosure logo Full Disclosure mailing list archives

Re: RX171104 Cscope v15.5 and minors - symlink vulnerability - advisory, exploit and patch.
From: rexolab <research () rexotec com>
Date: Thu, 18 Nov 2004 17:51:04 +0400

We are very serious in this matter as we already have discoused with you. We don't see why do  you think we are joking ?
We have found this vulnerability there's already eighteen month but we have find it in 15-4 release of cscope.
The 15-5 version has the same problem....


Release date of advisory's publication is looking only at us.....

About the patch, sorry, we made a mistake in sending you a wrong one, and now we are sending you the right one :

8<-------------------cut--here--------------------------------------------

diff -Naurp src_old/build.c src_new/build.c
--- src_old/build.c     2004-11-18 16:27:04.000000000 +0100
+++ src_new/build.c     2004-11-18 16:27:29.000000000 +0100
@@ -333,7 +333,7 @@ build(void)
                (void) fprintf(stderr, "cscope: cannot open file %s\n", reffile);
                myexit(1);
        }
-       if (invertedindex == YES && (postings = myfopen(temp1, "wb")) == NULL) {
+       if (invertedindex == YES && (postings = myfopen(temp1, "w+xb")) == NULL) {
                cannotwrite(temp1);
                cannotindex();
        }
diff -Naurp src_old/display.c src_new/display.c
--- src_old/display.c   2004-11-18 16:27:04.000000000 +0100
+++ src_new/display.c   2004-11-18 16:27:29.000000000 +0100
@@ -431,7 +431,7 @@ search(void)
                        findresult = (*f)(pattern);
                }
                else {
-                       if ((nonglobalrefs = myfopen(temp2, "wb")) == NULL) {
+                       if ((nonglobalrefs = myfopen(temp2, "w+xb")) == NULL) {
                                cannotopen(temp2);
                                return(NO);
                        }
@@ -754,13 +754,13 @@ BOOL
 writerefsfound(void)
 {
        if (refsfound == NULL) {
-               if ((refsfound = myfopen(temp1, "wb")) == NULL) {
+               if ((refsfound = myfopen(temp1, "w+xb")) == NULL) {
                        cannotopen(temp1);
                        return(NO);
                }
        } else {
                (void) fclose(refsfound);
-               if ( (refsfound = myfopen(temp1, "wb")) == NULL) {
+               if ( (refsfound = myfopen(temp1, "w+xb")) == NULL) {
                        postmsg("Cannot reopen temporary file");
                        return(NO);
                }

8<----------------------------------------------cut-here-----------------------------------

enjoy,

Mr Gangstuck & associates......


---
On Thu, 18 Nov 2004 12:42:33 +0100 (CET)
Hans-Bernhard Broeker <broeker () physik rwth-aachen de> wrote:

On Thu, 18 Nov 2004, rexolab wrote:

   VulnDiscovery:   2003/05/21
   Release Date :   2004/11/17

Surely you're joking, Mr. Gangstuck.  You can't seriously be telling us
you sat on this for no less than 18 months, without telling anybody about
it.

Actually, I somewhat doubt you even discovered this yourself --- what with
this very bug having been posted to cscope's bugtracker on 2004-11-09.

   Status       :   vendor has just been notified.

Actually, we've been notified 11 days ago, and apparently not by you.

   First, the temporary directory (P_tmpdir="/tmp") is badly handled 
   in every myfopen() internal call.

[... there doesn't seem to be a "second", to that first...]

Anyway, you're right, the vulnerability is there.  Unfortunately your
patch is not quite sufficient to close it, because you overlooked 
that temp2, one of the two predictable filenames, is also used to
construct an output redirection for a shell command run by cscope.

-- 
Hans-Bernhard Broeker (broeker () physik rwth-aachen de)
Even if all the snow were burnt, ashes would remain.



--
Ce message ne contient pas de virus connu.
neoDomaine Postmaster - http://www.neodomaine.com/


_______________________________________________
Full-Disclosure - We believe in it.
Charter: http://lists.netsys.com/full-disclosure-charter.html


  By Date           By Thread  

Current thread:
[ Nmap | Sec Tools | Mailing Lists | Site News | About/Contact | Advertising | Privacy ]
AlienVault