ports/128958: [vuxml] [patch] fix CVE-2008-3863 in
print/enscript-letter
Eygene Ryabinkin
rea-fbsd at codelabs.ru
Tue Nov 18 03:30:01 PST 2008
>Number: 128958
>Category: ports
>Synopsis: [vuxml] [patch] fix CVE-2008-3863 in print/enscript-letter
>Confidential: no
>Severity: serious
>Priority: high
>Responsible: freebsd-ports-bugs
>State: open
>Quarter:
>Keywords:
>Date-Required:
>Class: sw-bug
>Submitter-Id: current-users
>Arrival-Date: Tue Nov 18 11:30:01 UTC 2008
>Closed-Date:
>Last-Modified:
>Originator: Eygene Ryabinkin
>Release: FreeBSD 7.1-PRERELEASE amd64
>Organization:
Code Labs
>Environment:
System: FreeBSD 7.1-PRERELEASE amd64
>Description:
There is a stack-based overflow in the enscript escape codes handling
code.
Citing by the Secunia's report:
-----
The vulnerability is caused due to a boundary error within the
"read_special_escape()" function in src/psgen.c. This can be exploited
to cause a stack-based buffer overflow by tricking the user into
converting a malicious file.
Successful exploitation allows execution of arbitrary code, but
requires that special escapes processing is enabled with the "-e"
option.
-----
>How-To-Repeat:
http://secunia.com/secunia_research/2008-41/
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2008-3863
>Fix:
The following patch should introduce the fix to the FreeBSD port:
--- 1.6.4_1-to-1.6.4_2-fix-CVE-2008-4306.diff begins here ---
diff -urN ./Makefile ../enscript-letter/Makefile
--- ./Makefile 2008-11-18 13:57:48.000000000 +0300
+++ ../enscript-letter/Makefile 2008-11-18 13:58:02.000000000 +0300
@@ -7,7 +7,7 @@
PORTNAME= enscript
PORTVERSION= 1.6.4
-PORTREVISION= 1
+PORTREVISION= 2
CATEGORIES+= print
MASTER_SITES= http://www.codento.com/people/mtr/genscript/
PKGNAMESUFFIX= -${PAPERSIZE}
diff -urN ./files/patch-CVE-2008-3863-and-4306 ../enscript-letter/files/patch-CVE-2008-3863-and-4306
--- ./files/patch-CVE-2008-3863-and-4306 1970-01-01 03:00:00.000000000 +0300
+++ ../enscript-letter/files/patch-CVE-2008-3863-and-4306 2008-11-18 13:57:08.000000000 +0300
@@ -0,0 +1,94 @@
+Patch for CVE-2008-3863 and CVE-2008-4306
+
+Obtained from: http://cvs.fedoraproject.org/viewvc/devel/enscript/enscript-CVE-2008-3863%2BCVE-2008-4306.patch?revision=1.1
+
+--- src/psgen.c
++++ src/psgen.c 2008-10-29 10:43:08.512598143 +0100
+@@ -24,6 +24,7 @@
+ * Boston, MA 02111-1307, USA.
+ */
+
++#include <limits.h>
+ #include "gsint.h"
+
+ /*
+@@ -124,7 +125,7 @@ struct gs_token_st
+ double xscale;
+ double yscale;
+ int llx, lly, urx, ury; /* Bounding box. */
+- char filename[512];
++ char filename[PATH_MAX];
+ char *skipbuf;
+ unsigned int skipbuf_len;
+ unsigned int skipbuf_pos;
+@@ -135,11 +136,11 @@ struct gs_token_st
+ Color bgcolor;
+ struct
+ {
+- char name[512];
++ char name[PATH_MAX];
+ FontPoint size;
+ InputEncoding encoding;
+ } font;
+- char filename[512];
++ char filename[PATH_MAX];
+ } u;
+ };
+
+@@ -248,7 +249,7 @@ static int do_print = 1;
+ static int user_fontp = 0;
+
+ /* The user ^@font{}-defined font. */
+-static char user_font_name[256];
++static char user_font_name[PATH_MAX];
+ static FontPoint user_font_pt;
+ static InputEncoding user_font_encoding;
+
+@@ -978,7 +979,8 @@ large for page\n"),
+ FATAL ((stderr,
+ _("user font encoding can be only the system's default or `ps'")));
+
+- strcpy (user_font_name, token.u.font.name);
++ memset (user_font_name, 0, sizeof(user_font_name));
++ strncpy (user_font_name, token.u.font.name, sizeof(user_font_name) - 1);
+ user_font_pt.w = token.u.font.size.w;
+ user_font_pt.h = token.u.font.size.h;
+ user_font_encoding = token.u.font.encoding;
+@@ -1444,7 +1446,7 @@ read_special_escape (InputStream *is, To
+ buf[i] = ch;
+ if (i + 1 >= sizeof (buf))
+ FATAL ((stderr, _("too long argument for %s escape:\n%.*s"),
+- escapes[i].name, i, buf));
++ escapes[e].name, i, buf));
+ }
+ buf[i] = '\0';
+
+@@ -1452,7 +1454,8 @@ read_special_escape (InputStream *is, To
+ switch (escapes[e].escape)
+ {
+ case ESC_FONT:
+- strcpy (token->u.font.name, buf);
++ memset (token->u.font.name, 0, sizeof(token->u.font.name));
++ strncpy (token->u.font.name, buf, sizeof(token->u.font.name) - 1);
+
+ /* Check for the default font. */
+ if (strcmp (token->u.font.name, "default") == 0)
+@@ -1465,7 +1468,8 @@ read_special_escape (InputStream *is, To
+ FATAL ((stderr, _("malformed font spec for ^@font escape: %s"),
+ token->u.font.name));
+
+- strcpy (token->u.font.name, cp);
++ memset (token->u.font.name, 0, sizeof(token->u.font.name));
++ strncpy (token->u.font.name, cp, sizeof(token->u.font.name) - 1);
+ xfree (cp);
+ }
+ token->type = tFONT;
+@@ -1544,7 +1548,8 @@ read_special_escape (InputStream *is, To
+ break;
+
+ case ESC_SETFILENAME:
+- strcpy (token->u.filename, buf);
++ memset (token->u.filename, 0, sizeof(token->u.font.name));
++ strncpy (token->u.filename, buf, sizeof(token->u.filename) - 1);
+ token->type = tSETFILENAME;
+ break;
--- 1.6.4_1-to-1.6.4_2-fix-CVE-2008-4306.diff ends here ---
The following VuXML entry should be added:
--- vuln.xml begins here ---
<vuln vid="">
<topic>GNU enscript -- multiple vulnerabilities</topic>
<affects>
<package>
<name>enscript-letter</name>
<name>enscript-letterdj</name>
<name>enscript-a4</name>
<range><lt>1.6.4_2</lt></range>
</package>
</affects>
<description>
<body xmlns="http://www.w3.org/1999/xhtml">
<p>Ulf Harnhammar from Secunia Research had discovered stack-based
buffer overflow vulnerability in the GNU enscript code:</p>
<blockquote cite="http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2008-3863">
<p>Stack-based buffer overflow in the read_special_escape
function in src/psgen.c in GNU Enscript 1.6.1 and 1.6.4 beta,
when the -e (aka special escapes processing) option is enabled,
allows user-assisted remote attackers to execute arbitrary code
via a crafted ASCII file, related to the setfilename
command.</p>
</blockquote>
<p>CVE-2008-4306 is a Ubuntu-specific mirror issue for this
vulnerability.</p>
</body>
</description>
<references>
<cvename>CVE-2008-3863</cvename>
<cvename>CVE-2008-4306</cvename>
<url>http://secunia.com/secunia_research/2008-41/</url>
<url>http://cvs.fedoraproject.org/viewvc//devel/enscript/enscript-CVE-2008-3863+CVE-2008-4306.patch</url>
<url>https://launchpad.net/ubuntu/intrepid/+source/enscript/1.6.4-12ubuntu0.8.10.1</url>
</references>
<dates>
<discovery>2008-10-22</discovery>
</dates>
</vuln>
--- vuln.xml ends here ---
>Release-Note:
>Audit-Trail:
>Unformatted:
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