Buffer overflow in Amperecomputing Ampereone A128-34x

CVE-2025-62864

Ampere AmpereOne AC03 devices before 3.5.9.3, AmpereOne AC04 devices before 4.4.5.2, and AmpereOne M devices before 5.4.5.1 allow an incorrectly formed SMC call to UEFI-MM MMCommunicate service that could result in an out-of-bounds write within the UEFI-MM Secure Partition context.

Vulnerability class: Buffer Overflow

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.004 (27.9th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 28th percentile — 27.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2025-62864: held from 0.004 to 0.004.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: +0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-62864?
CVE-2025-62864 is a critical-severity vulnerability in Amperecomputing Ampereone A128-34x, classified under Out-of-bounds Write. CVSS score: 9.8/10. Published 2025-12-16.
How severe is CVE-2025-62864?
Critical severity. CVSS v3 base score is 9.8 out of 10.