CVE-2026-54333: theopolis uefi-firmware-parser · Out-of-bounds Write
Affects theopolis uefi-firmware-parserSource CVE Database V5
Not known to be exploited · CVSS 9.8 Critical : upgrade to 1.14 as a priority.
Data as of 30 Oct 2026, 06:59 UTC
- EPSS
- 0.8% chance of exploitation in 30 days – higher than 56% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 1.14
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 14 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
Upgrade uefi-firmware-parser and theopolis/uefi-firmware-parser to 1.14.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| theopolisuefi-firmware-parser | Affected
| Fixed in
|
GitHubtheopolis/uefi-firmware-parserpkg:github/theopolis/uefi-firmware-parserOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade to version 1.14 or later of theopolis uefi-firmware-parser where this vulnerability is fixed. No other mitigation or temporary workaround is indicated in the available data.
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.
References
- github.com/theopolis/uefi-firmware-parser/security/advisories/GHSA-2689-5p89-6j3j (opens in a new tab)
- github.com/theopolis/uefi-firmware-parser/pull/145 (opens in a new tab)
- github.com/theopolis/uefi-firmware-parser/commit/bf3dfaa8a05675bae6ea0cbfa082ddcebfcde23e (opens in a new tab)
- github.com/theopolis/uefi-firmware-parser/releases/tag/v1.14 (opens in a new tab)