Administrator takeover via auth-exempt password reset
Published Sep 7, 2026 · Updated Sep 8, 2026
Improper authentication in Tenda AC9 15.03.05.14 Web Management allows remote attackers to replace the administrator password. R7WebsSecurityHandler exempts the /goform/fast_setting prefix from authentication, after which the endpoint writes loginPwd to sys.userpass and commits it to flash. No credentials or user interaction are required; a successful request replaces the stored password and grants full router administration.
Summary
What happened
Improper authentication in Tenda AC9 15.03.05.14 Web Management allows remote attackers to replace the administrator password. R7WebsSecurityHandler exempts the /goform/fast_setting prefix from authentication, after which the endpoint writes loginPwd to sys.userpass and commits it to flash. No credentials or user interaction are required; a successful request replaces the stored password and grants full router administration.
The record
- CVE
- CVE-2026-86300
- Published
- Sep 7, 2026
- Updated
- Sep 8, 2026
- Vendor
- Shenzhen Tenda Technology Co., Ltd.
- Product
- AC9
- Classifications
- CWE-287, T1098, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 7, 2026CVE publishedPublication date reported by the CVE source.
- Sep 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?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=15.03.05.14
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
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 administrator password-change proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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