Buffer overflow in H3c Magic B3

CVE-2026-8764

A security vulnerability has been detected in H3C Magic B3 up to 100R002. This affects the function UpdateWanParams of the file /goform/aspForm. Such manipulation of the argument param leads to buffer overflow. The attack may be performed from remote. The exploit has been disclosed publicly and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

Vulnerability class: Buffer Overflow

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.2 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.009 (56.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 57th percentile — 56.6% 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-2026-8764: held from 0.005 to 0.009.

EPSS over last 30 days · oldest: 0.005 · newest: 0.009 · change: +0.004

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-8764?
CVE-2026-8764 is a high-severity vulnerability in H3c Magic B3, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 7.2/10. Published 2026-05-17.
How severe is CVE-2026-8764?
High severity. CVSS v3 base score is 7.2 out of 10.