Unauthenticated system-log disclosure via missing access checks
Published Feb 8, 2026 · Updated Feb 8, 2026
Improper access control in the Tenda AC21 16.03.08.16 web interface allows remote attackers to read system logs without authentication. The DownloadLog handler omits session and authorization checks, opens the device log, and streams its contents through /cgi-bin/DownloadLog. Any network client that can reach the management interface can retrieve internal addresses, MAC addresses, connection records, and diagnostic data; no configuration change or service interruption is reported.
Summary
What happened
Improper access control in the Tenda AC21 16.03.08.16 web interface allows remote attackers to read system logs without authentication. The DownloadLog handler omits session and authorization checks, opens the device log, and streams its contents through /cgi-bin/DownloadLog. Any network client that can reach the management interface can retrieve internal addresses, MAC addresses, connection records, and diagnostic data; no configuration change or service interruption is reported.
The record
- CVE
- CVE-2026-2147
- Published
- Feb 8, 2026
- Updated
- Feb 8, 2026
- Vendor
- Shenzhen Tenda Technology Co., Ltd.
- Product
- AC21 Firmware
- Classifications
- CWE-284, CWE-200, T1005
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Feb 8, 2026CVE publishedPublication date reported by the CVE source.
- Feb 8, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=16.03.08.16
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.
Weakness, pattern, technique
Public exploit references
- Unauthenticated system-log download proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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