Bug 224610

Summary: CVE-2007-0455 gd buffer overrun
Product: [Fedora] Fedora Reporter: Josh Bressers <bressers>
Component: gdAssignee: Ivana Varekova <varekova>
Status: CLOSED ERRATA QA Contact:
Severity: medium Docs Contact:
Priority: low    
Version: 6Keywords: Security
Target Milestone: ---   
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard: impact=low,source=vendorsec,reported=20070124,public=20070126
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2007-01-29 09:25:02 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description Josh Bressers 2007-01-26 17:53:19 UTC 
+++ This bug was initially created as a clone of Bug #224607 +++

Kees Cook from Ubuntu reported a "off-the-end-of-string increment", which could
theoretically lead ot a buffer overflow.

This flaw would only be exploitable if a JIS-encoded font is used when
processing a special malicious string.

The issue here is that the NULL terminator is incremented, which could lead to
unknown results during the processing of the malicious string.

Index: gdft.c
===================================================================
RCS file: /repository/gd/libgd/gdft.c,v
retrieving revision 1.28
diff -u -p -r1.28 gdft.c
--- gdft.c      3 Jan 2007 21:21:21 -0000       1.28
+++ gdft.c      24 Jan 2007 23:00:55 -0000
@@ -1178,7 +1178,7 @@ fprintf(stderr,"dpi=%d,%d metric_res=%d 
                {
                  ch = c & 0xFF;        /* don't extend sign */
                }
-             next++;
+             if (*next) next++;
            }
            break;
          case gdFTEX_Big5:

This flaw also affects FC5
Comment 1 Ivana Varekova 2007-01-29 09:25:02 UTC 
Fixed in gd-2.0.33-12.fc7 in devel branch (gd-2.0.33-10.fc6 - in fc6,
gd-2.0.33-7.fc5 in fc5)