Admin-session theft via unescaped DHCP hostnames
Published Dec 9, 2025 · Updated Dec 10, 2025
Stored XSS in Mercury MR816v2 firmware 081C3114 4.8.7 Build 110427 Rel 36550n allows remote attackers on the LAN to steal admin sessions. The DHCP service stores a client-supplied hostname, and the management UI inserts it into the device list without HTML encoding, causing embedded JavaScript to execute in the administrator’s browser. The required gate is LAN access plus an active administrator session; the script then operates under the management origin to exfiltrate session material or issue administrative requests.
Summary
What happened
Stored XSS in Mercury MR816v2 firmware 081C3114 4.8.7 Build 110427 Rel 36550n allows remote attackers on the LAN to steal admin sessions. The DHCP service stores a client-supplied hostname, and the management UI inserts it into the device list without HTML encoding, causing embedded JavaScript to execute in the administrator’s browser. The required gate is LAN access plus an active administrator session; the script then operates under the management origin to exfiltrate session material or issue administrative requests.
The record
- CVE
- CVE-2025-65289
- Published
- Dec 9, 2025
- Updated
- Dec 10, 2025
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-79, T1189
- Attack vector
- adjacent
- Privileges
- unauthenticated
Timeline
How it unfolded
- Dec 9, 2025CVE publishedPublication date reported by the CVE source.
- Dec 10, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- DHCP hostname stored-XSS proof of conceptproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo