An out-of heap-based buffer write flaw was found in the way TrueType bytecode / opcode interpreter of the FreeType font rendering engine performed moving of zone2 pointer point by execution of 'SHift Contour' (SHC) instruction. A remote attacker could provide a specially-crafted font file, which once opened in an application linked against FreeType would lead to that application crash, or, potentially arbitrary code execution with the privileges of the user running the application.

Upstream bug report: [1] https://savannah.nongnu.org/bugs/?35689

Upstream patch: [2] http://git.savannah.gnu.org/cgit/freetype/freetype2.git/commit/?id=0fc8debeb6c2f6a8a9a2b97332a7c8a0a1bd9e85

Acknowledgements:

Red Hat would like to thank Mateusz Jurczyk of the Google Security Team for reporting this issue.

An out-of heap-based buffer write flaw was found in the way FreeType font rendering engine performed parsing of glyph information and bitmaps for certain glyph bitmap distribution format (BDF) fonts. A remote attacker could provide a specially-crafted BDF font file, which once opened in an application linked against FreeType would lead to that application crash, or, potentially, arbitrary code execution with the privileges of the user running the application.

Upstream bug report: [1] https://savannah.nongnu.org/bugs/?35607

Upstream patch: [2] http://git.savannah.gnu.org/cgit/freetype/freetype2.git/commit/?id=28dd2c45957278e962f95633157b6139de8170aa

Acknowledgements:

Red Hat would like to thank Mateusz Jurczyk of the Google Security Team for reporting this issue.

An array index error, leading to heap-based buffer overflow was found in the way the FreeType font rendering engine processed FontType42 font files with negative length of certain special font name table strings. An attacker could use this flaw to create a specially-crafted font file (which bypasses a size check and triggers a heap-based buffer overflow). Such file, when opened, would cause an application linked against libfreetype to crash, or, possibly execute arbitrary code.

Upstream bug report: [1] https://savannah.nongnu.org/bugs/?30656 Public reproducer: [2] http://alt.swiecki.net/j/f/sigsegv29.ttf Upstream changeset: [3] http://git.savannah.gnu.org/cgit/freetype/freetype2.git/commit/?id=c06da1ad34663da7b6fc39b030dc3ae185b96557

A stack-based buffer overflow was found in the way FreeType font rendering engine processed certain Adobe Type 1 Mac Font File (LWFN) fonts. An attacker could use this flaw to create a specially-crafted font file that, when opened, would cause an application linked against libfreetype to crash, or, possibly execute arbitrary code.

Upstream bug report: [1] https://savannah.nongnu.org/bugs/?30658

Public reproducer: [2] http://alt.swiecki.net/j/f/sigsegv31.ttf

Upstream changeset: [3] http://git.savannah.gnu.org/cgit/freetype/freetype2.git/commit/?id=81f3472c0ba7b8f6466e2e214fa8c1c17fade975

Credit: Robert Swiecki