{"id":"CVE-2026-91189","revision":"fe0aec5dcb714c578ed4932225e9e8c8","records":[{"revision":"fe0aec5dcb714c578ed4932225e9e8c8","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-91189","aliases":[],"title":"GUIX binary resource loader: unvalidated glyph range causes an integer underflow and a heap out-of-bounds write when loading an untrusted font or theme","description":"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.\n\n\n\nThat 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.","state":0,"publishedAt":"2026-10-20T14:53:44.86+00:00","modifiedAt":"2026-10-20T15:25:24.066+00:00","affected":[{"ecosystem":"Vendor product","name":"GUIX","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Eclipse Foundation\",\n                    \"product\": \"Eclipse ThreadX - GUIX\",\n                    \"packageName\": \"GUIX\",\n                    \"versions\": [\n                        {\n                            \"status\": \"affected\",\n                            \"version\": \"0\",\n                            \"lessThanOrEqual\": \"6.5.1.202602a\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"status\": \"unaffected\",\n                            \"version\": \"6.5.2.202603\"\n                        }\n                    ],\n                    \"defaultStatus\": \"unaffected\"\n                }"}],"metrics":[{"system":"CVSS 4.0","vector":"CVSS:4.0/AV:L/AC:H/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","score":7.1,"severity":"HIGH"}],"references":["https://github.com/eclipse-threadx/guix/security/advisories/GHSA-hgcj-22cg-4hfv"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-91189","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-91189","identifiers":["CVE-2026-91189"]},"retained":false,"historicalAffected":[]}],"coverage":[]}