Unauthorized access via reusable session cookie
Published Dec 31, 2025 · Updated Dec 31, 2025
Insufficient session expiration in KZ Broadband CPE firmware allows remote attackers to retain unauthorized management access. The web interface accepts a previously issued uid token cookie on /status.html after the session should have expired, rather than invalidating it. Exploitation requires possession of an old token and exposes management information available to that session without fresh authentication.
Summary
What happened
Insufficient session expiration in KZ Broadband CPE firmware allows remote attackers to retain unauthorized management access. The web interface accepts a previously issued uid token cookie on /status.html after the session should have expired, rather than invalidating it. Exploitation requires possession of an old token and exposes management information available to that session without fresh authentication.
The record
- CVE
- CVE-2021-47740
- Published
- Dec 31, 2025
- Updated
- Dec 31, 2025
- Vendor
- KZ Broadband Technologies, Ltd.
- Product
- AM5000W
- Classifications
- CWE-613, T1550.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Dec 31, 2025CVE publishedPublication date reported by the CVE source.
- Dec 31, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=2.0.0B3037
What conditions does exploitation require?
What is affected?
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.
Public exploit references
- Packet Storm Security exploit entry 161892proof of concept · unverified
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Technologies
Your stack
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Your stack
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