Attack Chain

1. The attacker identifies an H3C SecPath F1000-C8300 appliance exposed to the internet.
2. The attacker crafts a malicious HTTP POST request targeting the /webui/?g=log_fw_nbc_mail_jsondata endpoint on the vulnerable appliance.
3. The request includes a specially crafted subject argument containing SQL injection payloads designed to bypass input validation.
4. The vulnerable appliance processes the request, and the malicious SQL payload is executed within the application's backend database query.
5. Successful exploitation grants the attacker the ability to read, modify, or delete sensitive information stored in the appliance's database.
6. Depending on the database's capabilities and privileges, the attacker may escalate the compromise to achieve remote code execution on the device, leading to full system control.
7. The final objective could range from data exfiltration to establishing persistent access or using the compromised appliance as a pivot point for further attacks within the network.

Impact

Successful exploitation of CVE-2026-15907 can lead to severe consequences for organizations utilizing H3C SecPath F1000-C8300 appliances. Attackers can gain unauthorized access to sensitive configuration data, user credentials, or network logs stored in the device's database. This data could be exfiltrated, altered, or deleted, leading to data breaches, operational disruptions, or integrity compromises. Furthermore, if the SQL injection can be leveraged for remote code execution, attackers could gain complete control over the firewall, potentially allowing them to modify network rules, redirect traffic, establish backdoors, or move laterally into internal networks. The remote nature of the vulnerability and the public availability of an exploit increase the likelihood of widespread targeting.

Recommendation

• Patch CVE-2026-15907 immediately: Monitor the official H3C channels for the release of the technical fix and apply it to all affected SecPath F1000-C8300 appliances (up to version 20260522) as soon as it becomes available.
• Deploy the Sigma rules in this brief: Implement the provided Sigma rule to your SIEM solution to detect exploitation attempts against the /webui/?g=log_fw_nbc_mail_jsondata endpoint.
• Enable web server logging: Ensure comprehensive logging is enabled for your H3C appliance's web server, specifically capturing full HTTP request details, including URI stems, query parameters, and methods, to activate the rule above.
• Review network security policies: Restrict administrative access to H3C SecPath F1000-C8300 appliances from untrusted networks where possible.