Description
A heap-buffer-overflow vulnerability exists in the nothings stb TrueType library, up to version 1.26, that is used for parsing TrueType font files. The vulnerability exists in the stbtt__GetGlyphShapeTT() function within the nothings stb_truetype.h library when parsing malformed TTF (TrueType Font) files. The vulnerability resides in the glyph data parsing path. An attacker can craft a malformed TTF file with an inflated endPtsOfContours value and truncate the remaining glyph data. When an application utilizing stb_truetype.h (such as various game engines or graphics software) attempts to load, bake, or render this malformed font via stbtt_GetGlyphShape(), the parser will attempt to read past the end of the glyph data buffer, triggering the out-of-bounds read.
References6
Metrics
- CVSS 3.1
-
7.1
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H - EPSS — exploit probability
- 0% percentile: 7 · as of 12 November 2026
- CWE
- CWE-122
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