What is CVE-2014-4859?

CVE-2014-4859 is a medium-severity vulnerability in American Megatrends Incorporated (Ami) Bios, classified under Integer Overflow or Wraparound. CVSS score: 6.8/10. Published 2020-01-31.

How severe is CVE-2014-4859?

Medium severity. CVSS v3 base score is 6.8 out of 10.

Integer overflow in American Megatrends Incorporated (Ami) Bios

CVE-2014-4859

Integer overflow in the Drive Execution Environment (DXE) phase in the Capsule Update feature in the UEFI implementation in EDK2 allows physically proximate attackers to bypass intended access restrictions via crafted data.

Vulnerability class: Integer Overflow

Published 2020-01-31 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.8 (Medium). Vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.006 (45.9th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 46th percentile — 45.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000

Affected products

American Megatrends Incorporated (Ami) Bios
Phoenix Technologies Ltd. Sct3 — versions before 5/23/2014
Tianocore Edk2

Weakness classification (CWE)

CWE-190 — Integer Overflow or Wraparound

References

www.kb.cert.org/vuls/id/552286 (US Government Resource, Third Party Advisory)

Frequently asked questions

What is CVE-2014-4859?: CVE-2014-4859 is a medium-severity vulnerability in American Megatrends Incorporated (Ami) Bios, classified under Integer Overflow or Wraparound. CVSS score: 6.8/10. Published 2020-01-31.
How severe is CVE-2014-4859?: Medium severity. CVSS v3 base score is 6.8 out of 10.