Track vulnerabilities like this one.
Sign up free to get alerted when software you use is affected.
9.8
CVE-2026-54334: UEFI Firmware Parser can crash and allow code execution
CVE-2026-54334 · published 28 days ago
Summary
Versions of the UEFI Firmware Parser before 1.14 can be fooled by specially crafted BIOS or firmware files. The parser may write beyond its internal memory area, causing the program to stop working and, in some cases, run attacker‑controlled code. Updating to version 1.14 or later fixes the problem.
What to do
The CVE record does not list a fixed version. Check the vendor's site or the advisory links below - a fix may already be released.
Affected software
| Vendor | Product | Affected versions |
|---|---|---|
| theopolis | uefi-firmware-parser | < 1.14 |
Original advisory text
UEFI Firmware Parser: Heap out-of-bounds write in tiano decompressor `ReadCLen`
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->mCLen heap array because its loop does not enforce Index < NC. The CharC == 2 run-length path can additionally request up to 531 zero writes through Sd->mCLen[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.
References
Internet-facing
3 days
Internal
60 days
- Not known to be exploited
- Can be exploited automatically
- Gives an attacker full control
Type
CWE-787Out-of-bounds Write
Timeline
Published14 Sep 2026
Updated11 Oct 2026
First seen14 Sep 2026
Track software like this
Free during beta