Buffer Overflow in H3C Magic B3 Router by H3C Technologies
CVE-2026-8764

8.6HIGH

Key Information:

Vendor

H3c
Status
Magic B3
Vendor
CVE Published:
17 May 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-8764?

A security vulnerability has been identified in the H3C Magic B3 router, specifically in the UpdateWanParams function within the /goform/aspForm file. This flaw enables attackers to manipulate parameters, resulting in a potential buffer overflow. The attack can be executed remotely, posing a significant risk as the exploit details have been publicly disclosed. Despite early notifications to H3C Technologies, there has been no response or mitigation from the vendor.

Affected Version(s)

Magic B3 100R002

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-8764 - Proof of Concept

References

https://vuldb.com/vuln/364389
vdb-entrytechnical-description
https://vuldb.com/vuln/364389/cti
signaturepermissions-required
https://vuldb.com/submit/811373
third-party-advisory

CVSS V4

Score:
8.6
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

yyy0032 (VulDB User)
VulDB CNA Team
.