CVE-2015-1802

The bdf parser reads a count for the number of properties defined in a font from the font file, and allocates arrays with entries for each property based on that count. It never checked to see if that count was negative, or large enough to overflow when multiplied by the size of the structures being allocated, and could thus allocate the wrong buffer size, leading to out of bounds writes (CVE-2015-1802).

If the bdf parser failed to parse the data for the bitmap for any character, it would proceed with an invalid pointer to the bitmap data and later crash when trying to read the bitmap from that pointer (CVE-2015-1803).

The bdf parser read metrics values as 32-bit integers, but stored them into 16-bit integers. Overflows could occur in various operations leading to out-of-bounds memory access (CVE-2015-1804).

These are all security issues fixed in the libXfont-devel-1.5.2-1.1 package on the GA media of openSUSE Tumbleweed.

xorg-x11-libs was patched to fix the following security issues:

* Integer overflow of allocations in font metadata file parsing.
  (CVE-2014-0209)
* libxfont not validating length fields when parsing xfs protocol
  replies. (CVE-2014-0210)
* Integer overflows causing miscalculating memory needs for xfs
  replies. (CVE-2014-0211)

Further information is available at http://lists.x.org/archives/xorg-announce/2014-May/002431.html http://lists.x.org/archives/xorg-announce/2014-May/002431.html .

Security Issues references:

* CVE-2014-0209
  <http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2014-0209>
* CVE-2014-0210
  <http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2014-0210>
* CVE-2014-0211
  <http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2014-0211>

LibXFont was updated to fix security problems.

Following security issues were fixed:

• CVE-2015-1802: The bdf parser reads a count for the number of properties defined in a font from the font file, and allocates arrays with entries for each property based on that count. It never checked to see if that count was negative, or large enough to overflow when multiplied by the size of the structures being allocated, and could thus allocate the wrong buffer size, leading to out of bounds writes.

• CVE-2015-1803: If the bdf parser failed to parse the data for the bitmap for any character, it would proceed with an invalid pointer to the bitmap data and later crash when trying to read the bitmap from that pointer.

• CVE-2015-1804: The bdf parser read metrics values as 32-bit integers, but stored them into 16-bit integers. Overflows could occur in various operations leading to out-of-bounds memory access.

The bdfReadProperties function in bitmap/bdfread.c in X.Org libXfont before 1.4.9 and 1.5.x before 1.5.1 allows remote authenticated users to cause a denial of service (out-of-bounds write and crash) or possibly execute arbitrary code via a (1) negative or (2) large property count in a BDF font file.

Ilja van Sprundel, Alan Coopersmith, and William Robinet discovered that libXfont incorrectly handled malformed bdf fonts. A local attacker could use this issue to cause libXfont to crash, or possibly execute arbitrary code in order to gain privileges.