Vulnerability · Published May 17, 2026 · Assigned by VulDB

CVE-2026-8764H3C Magic B3 aspForm UpdateWanParams buffer overflow

High 7.2

In plain English

A high-severity buffer overflow in Magic B3 from H3C. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 42% of all known vulnerabilities).

Severity (CVSS 3.1)7.2High

Exploit odds (30 days)0.5%top 58.4% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

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.

Affected products (as reported)

Vendor	Product	Versions
H3C	Magic B3	100R002

Weakness: CWE-120, CWE-119 · Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:R

References

VDB-364389 | H3C Magic B3 aspForm UpdateWanParams buffer overflow vdb-entry, technical-description
VDB-364389 | CTI Indicators (IOB, IOC, IOA) signature, permissions-required
Submit #811373 | New H3C Technologies Co., Ltd. H3C Magic B3 <= 100R002 Buffer Overflow third-party-advisory
https://github.com/yyyy0031/CVE/issues/1 exploit, issue-tracking