CVE-2026-91189

The GUIX binary resource loader never checks that a font page's glyph range is well formed. `gx_page_header_first_glyph` and `gx_page_header_last_glyph` are read verbatim from the file and only the upper bound of `last_glyph` is validated, so a page declaring `first_glyph > last_glyph` makes `last - first + 1` underflow to a very large unsigned count. That count is multiplied by a glyph record size to reserve the load buffer, and the multiply is unchecked, so it wraps to a small value and the loader allocates a buffer far smaller than the data it is about to write. The load pass then recomputes the count in a narrower type and writes attacker-controlled glyph records into the undersized buffer.

CVSS

No CVSS.

References

Link	Resource
https://github.com/eclipse-threadx/guix/security/advisories/GHSA-hgcj-22cg-4hfv

Configurations

No configuration.

History

20 Oct 2026, 15:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-20 15:17

Updated : 2026-10-20 19:48

NVD link : CVE-2026-91189

Mitre link : CVE-2026-91189

CVE.ORG link : CVE-2026-91189

JSON object : View

Products Affected

No product.

CWE

CWE-190

Integer Overflow or Wraparound

CWE-680

Integer Overflow to Buffer Overflow

CWE-787

Out-of-bounds Write

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