ThorVG: Out-of-bounds Read in SFNT/TTF Font Loader via Memory API
Impact
Thor Vector Graphics (ThorVG) is a production-ready vector graphics engine. Prior to 1.0.7, the SFNT/TTF font loader's SfntLoader::gen function in tvgSfntLoader.cpp reads data[0] through data[3] to identify the font type without first checking that the input buffer contains at least four bytes. Loading an undersized font directly from memory through public APIs such as tvg::Text::load causes an out-of-bounds read. Loading through a file path using mmap can mask the read because of page alignment; the memory-loading API directly exposes it. Depending on memory layout, a malformed short font…
Source excerpt · GitHub_MAffected packages
Affected products
Vendor version evidence. Product records are separate from automatic dependency matching.
thorvg · thorvg
| Version / range | Source status |
|---|---|
| < 1.0.7 | affected |
Original source description
Thor Vector Graphics (ThorVG) is a production-ready vector graphics engine. Prior to 1.0.7, the SFNT/TTF font loader's SfntLoader::gen function in tvgSfntLoader.cpp reads data[0] through data[3] to identify the font type without first checking that the input buffer contains at least four bytes. Loading an undersized font directly from memory through public APIs such as tvg::Text::load causes an out-of-bounds read. Loading through a file path using mmap can mask the read because of page alignment; the memory-loading API directly exposes it. Depending on memory layout, a malformed short font may crash the consuming application or disclose adjacent heap memory. This issue is fixed in version 1.0.7.