CVE-2026-18497

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.

CVSS v3 7.1 HIGH

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.2

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://cwe.mitre.org/data/definitions/122.html
https://github.com/nothings/stb
https://github.com/nothings/stb/issues/1905
https://kb.cert.org/vuls/id/987105
https://www.kb.cert.org/vuls/id/987105
https://github.com/nothings/stb/issues/1905

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-07 15:16

Updated : 2026-09-08 14:07

NVD link : CVE-2026-18497

Mitre link : CVE-2026-18497

CVE.ORG link : CVE-2026-18497

JSON object : View

Products Affected

No product.

CWE

CWE-122

Heap-based Buffer Overflow

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