{"answers":{"affected":"3 open source packages ship an affected version, including uefi-firmware.","exploited":"There is no known exploitation of CVE-2026-54334 in the wild and no public exploit code.","fix":"No fix has been published for CVE-2026-54334 yet. Limit exposure of the affected software until one is available.","what":"CVE-2026-54334 is a critical memory corruption vulnerability in theopolis uefi-firmware-parser, published on 14 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-54334 and fix it if it is affected.\n\nWhat it is: CVE-2026-54334 is a critical memory corruption vulnerability in theopolis uefi-firmware-parser, published on 14 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2026-54334 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- uefi-firmware (PyPI): affected all versions up to 1.12; no fix listed\n- uefi-firmware (PyPI): affected all versions up to 1.12; no fix listed\n- uefi-firmware (PyPI): affected all versions up to 1.12; no fix listed\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-54334/ (Markdown: https://insights.sbomify.com/CVE-2026-54334/index.md)","id":"CVE-2026-54334","markdown":"https://insights.sbomify.com/CVE-2026-54334/index.md","name":"CVE-2026-54334","record":{"aliases":["GHSA-hm2w-vr2p-hq7w","PYSEC-2026-3394"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["code_execution","denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"UEFI firmware parser","requires_auth":"none","summary":"A heap out-of-bounds write in the Tiano decompressor allows attackers to crash the parser or potentially execute code via crafted firmware images.","user_interaction":"not_required","vuln_class":"memory_corruption"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[],"cvss":{"score":9.8,"severity":"critical","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"cwes":[{"id":"CWE-787","name":"Out-of-bounds Write"}],"description":"UEFI Firmware Parser parses BIOS, Intel ME, and UEFI firmware structures including volumes, file systems, and files. Prior to 1.14, ReadCLen() in uefi_firmware/compression/Tiano/Decompress.c reads Number from GetBits(Sd, CBIT) with CBIT = 9 and can obtain 511 entries for the 510-element Sd-\u003emCLen heap array because its loop does not enforce Index \u003c NC. The CharC == 2 run-length path can additionally request up to 531 zero writes through Sd-\u003emCLen[Index++] = 0. The normal CompressedSection.process() to efi_compressor.TianoDecompress() to TianoDecompress() to DecodeC() to ReadCLen() parsing path therefore permits crafted Tiano or EFI compressed firmware to corrupt heap memory, deterministically crash the parsing process, and potentially execute code depending on build and runtime details. This issue is fixed in version 1.14.","ecosystems":["PyPI"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":false,"headline":"UEFI Firmware Parser: Heap out-of-bounds write in tiano decompressor `ReadCLen`","id":"CVE-2026-54334","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"PyPI","product":null,"products":[],"type":"memory_corruption","year":"2026"},"n_packages":3,"n_references":4,"next":{"headline":"Feathersjs: Prototype pollution in @feathersjs/commons _.merge via JSON-parsed __proto__","id":"CVE-2026-54335"},"packages":[{"ecosystem":"PyPI","fixed":[],"introduced":["0"],"last_affected":["1.12"],"package":"uefi-firmware","purl":null,"source":"GHSA-hm2w-vr2p-hq7w"},{"ecosystem":"PyPI","fixed":[],"introduced":["0"],"last_affected":["1.12"],"package":"uefi-firmware","purl":"pkg:pypi/uefi-firmware","source":"GHSA-hm2w-vr2p-hq7w"},{"ecosystem":"PyPI","fixed":[],"introduced":["0"],"last_affected":["1.12"],"package":"uefi-firmware","purl":"pkg:pypi/uefi-firmware","source":"PYSEC-2026-3394"}],"prev":{"headline":"UEFI Firmware Parser: Stack out-of-bounds write in tiano decompressor MakeTable","id":"CVE-2026-54333"},"products":["uefi-firmware-parser"],"published":"2026-09-14","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"class":"attribution","licence":"CC BY 4.0","name":"PyPA Advisory Database","prefix":"PYSEC"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"yes","exploitation":"none","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-09-16","vendors":["theopolis"]},"summary":"A heap out-of-bounds write in the Tiano decompressor allows attackers to crash the parser or potentially execute code via crafted firmware images.","url":"https://insights.sbomify.com/CVE-2026-54334/"}