PatchSiren cyber security CVE debrief
CVE-2026-8764 Unknown Vendor CVE debrief
CVE-2026-8764 describes a buffer overflow in the UpdateWanParams function exposed through /goform/aspForm on H3C Magic B3 devices up to 100R002. The issue is described as remotely reachable and publicly disclosed, which raises the urgency for anyone running the affected firmware range. The NVD record was published on 2026-05-17 and lists the issue as High severity.
- Vendor
- Unknown Vendor
- Product
- Unknown
- CVSS
- HIGH 7.3
- CISA KEV
- Not listed in stored evidence
- Original CVE published
- 2026-05-17
- Original CVE updated
- 2026-05-18
- Advisory published
- 2026-05-17
- Advisory updated
- 2026-05-18
Who should care
Administrators and security teams responsible for H3C Magic B3 devices, especially if the management or WAN configuration interface is reachable from untrusted networks. Network defenders, incident responders, and asset owners should also treat this as a priority if they cannot quickly confirm firmware exposure.
Technical summary
The CVE source describes a parameter-manipulation flaw in UpdateWanParams within /goform/aspForm that can trigger a buffer overflow. NVD maps the weakness to CWE-119 and CWE-120 and assigns CVSS v4.0 7.3/High with a network attack vector. The supplied description says the exploit was publicly disclosed and that the vendor was contacted early without response.
Defensive priority
High
Recommended defensive actions
- Identify all H3C Magic B3 devices and confirm whether any run firmware up to 100R002.
- Restrict access to the device management and WAN configuration interfaces from untrusted networks.
- Apply a vendor-provided fix or firmware update if one becomes available; if none exists, plan compensating controls or replacement.
- Monitor device logs and network telemetry for abnormal requests to /goform/aspForm and related management endpoints.
- If exposure cannot be reduced quickly, isolate the device segment and treat it as a potential incident-response priority.
Evidence notes
The debrief is based on the CVE description and the NVD record published on 2026-05-17. The supplied source metadata includes references to a GitHub issue, a VulDB submission page, a VulDB vulnerability entry, and a VulDB CTI page. NVD lists the weaknesses as CWE-119 and CWE-120 and provides CVSS v4.0 7.3/High. The source description explicitly states that the exploit was publicly disclosed and that the vendor did not respond to early contact.
Official resources
Published in the NVD record on 2026-05-17. The source references a public GitHub issue and VulDB pages, and the description says the vendor was contacted early but did not respond.