{"cve":"CVE-2026-54333","nvd":{"published":"2026-09-14T20:16:45.990","modified":"2026-09-30T17:51:56.193","status":"Deferred","description":"UEFI Firmware Parser parses BIOS, Intel ME, and UEFI firmware structures including volumes, file systems, and files. Prior to 1.14, MakeTable() in uefi_firmware/compression/Tiano/Decompress.c does not validate that bit-length values read from a crafted Tiano or EFI compressed firmware bitstream remain within the expected range from 0 through 16. The normal CompressedSection.process() to efi_compressor.TianoDecompress() to TianoDecompress() to ReadPTLen() to MakeTable() parsing path can consequently write beyond the stack-allocated Count[17] array and related decode tables. The resulting stack corruption deterministically crashes the parsing process and may permit code execution depending on build and runtime details. This issue is fixed in version 1.14.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":9.8},"cwes":["CWE-787"],"references":["https://github.com/theopolis/uefi-firmware-parser/commit/bf3dfaa8a05675bae6ea0cbfa082ddcebfcde23e","https://github.com/theopolis/uefi-firmware-parser/pull/145","https://github.com/theopolis/uefi-firmware-parser/releases/tag/v1.14","https://github.com/theopolis/uefi-firmware-parser/security/advisories/GHSA-2689-5p89-6j3j"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:53:43.293028046+00:00"},"epss":{"cve":"CVE-2026-54333","score":0.00801,"percentile":0.56357,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-2689-5p89-6j3j","url":"https://osv.dev/vulnerability/GHSA-2689-5p89-6j3j","summary":"UEFI Firmware Parser has a stack out-of-bounds write in tiano decompressor MakeTable","modified":"2026-07-13T16:42:27.260242973Z","packages":[{"ecosystem":"PyPI","name":"uefi-firmware","purl":"pkg:pypi/uefi-firmware","ranges":["<=1.12"],"fixed":[]}]},{"id":"PYSEC-2026-3393","url":"https://osv.dev/vulnerability/PYSEC-2026-3393","summary":"UEFI Firmware Parser has a stack out-of-bounds write in tiano decompressor MakeTable","modified":"2026-07-13T16:33:27.535884043Z","packages":[{"ecosystem":"PyPI","name":"uefi-firmware","purl":"pkg:pypi/uefi-firmware","ranges":["<=1.12"],"fixed":[]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}