Common Vulnerabilities and Exposures assigned CVE-2014-9656 to the following issue:
The tt_sbit_decoder_load_image function in sfnt/ttsbit.c in FreeType before
2.5.4 does not properly check for an integer overflow, which allows remote
attackers to cause a denial of service (out-of-bounds read) or possibly have
unspecified other impact via a crafted OpenType font.
Created freetype tracking bugs for this issue:
Affects: fedora-all [bug 1191099]
Upstream bug is:
Issue was fixed upstream in 2.5.4.
This is an integer underflow issue in an integer overflow check, which guards against buffer over-read. This can easily trigger crash.
The problem was introduced in the following commit:
Additionally, prior to upstream version 2.5, affected code was only built and used when FT_CONFIG_OPTION_OLD_INTERNALS macro was not defined. It was defined by default in upstream versions prior to 2.4.12:
The freetype packages in Red Hat Enterprise Linux are based on older upstream versions and do not override this upstream setting, i.e. they define FT_CONFIG_OPTION_OLD_INTERNALS. Therefore, they were not affected by this issue, or the problem commit e4ecce3b attempted to address.
This issue did not affect the versions of freetype as shipped with Red Hat Enterprise Linux 5, 6, and 7.