{"id":"CVE-2021-32030","published":"2021-05-06T15:15:07Z","modified":"2026-06-17T03:52:42Z","title":"ASUS Routers Improper Authentication Vulnerability","vendor":"ASUS","product":"Routers","tier":"core","eol":null,"description":{"text":"The administrator application on ASUS GT-AC2900 devices before 3.0.0.4.386.42643 and Lyra Mini before 3.0.0.4_384_46630 allows authentication bypass when processing remote input from an unauthenticated user, leading to unauthorized access to the administrator interface. This relates to handle_request in router/httpd/httpd.c and auth_check in web_hook.o. An attacker-supplied value of '\\0' matches the device's default value of '\\0' in some situations. Note: All versions of Lyra Mini and earlier which are unsupported (End-of-Life, EOL) are also affected by this vulnerability, Consumers can mitigate this vulnerability by disabling the remote access features from WAN.","provenance":"source","from":"NVD"},"summary":{"text":"The administrator application on ASUS GT-AC2900 routers (before 3.0.0.4.386.42643) and Lyra Mini devices (before 3.0.0.4_384_46630) fails to properly authenticate requests, leaving the administrator interface exposed. An unauthenticated remote attacker can reach the administrator interface by sending crafted input, because an attacker-supplied value of '\\0' matches the device's default value in some situations, and no user interaction or prior credentials are needed.","provenance":"ai","model":"claude-haiku-5-5","generatedAt":"2026-10-23T07:09:32Z"},"cvss":{"score":9.8,"severity":"CRITICAL","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","provenance":"source","from":"NVD"},"epss":{"score":0.99393,"percentile":0.9994,"date":"2026-10-29","provenance":"source"},"kev":{"dateAdded":"2025-06-02","dueDate":"2025-06-23","ransomware":false,"requiredAction":"Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.","notes":"https://www.asus.com/us/supportonly/lyra%20mini/helpdesk_bios/ ; https://www.asus.com/us/supportonly/rog%20rapture%20gt-ac2900/helpdesk_bios/; https://nvd.nist.gov/vuln/detail/CVE-2021-32030","provenance":"source"},"vulncheckKev":{"dateAdded":"2023-11-16","exploitedFirstSeen":"2023-11-16","ransomware":false,"evidence":[{"url":"https://dashboard.shadowserver.org/statistics/honeypot/vulnerability/map/?day=2023-11-16&host_type=src&vulnerability=cve-2021-32030","date":"2023-11-16"},{"url":"https://dashboard.shadowserver.org/statistics/honeypot/vulnerability/map/?day=2023-11-18&host_type=src&vulnerability=cve-2021-32030","date":"2023-11-18"},{"url":"https://dashboard.shadowserver.org/statistics/honeypot/vulnerability/map/?day=2023-11-23&host_type=src&vulnerability=cve-2021-32030","date":"2023-11-23"},{"url":"https://dashboard.shadowserver.org/statistics/honeypot/vulnerability/map/?day=2023-11-26&host_type=src&vulnerability=cve-2021-32030","date":"2023-11-26"},{"url":"https://dashboard.shadowserver.org/statistics/honeypot/vulnerability/map/?day=2023-12-24&host_type=src&vulnerability=cve-2021-32030","date":"2023-12-24"},{"url":"https://dashboard.shadowserver.org/statistics/honeypot/vulnerability/map/?day=2024-01-22&host_type=src&vulnerability=cve-2021-32030","date":"2024-01-22"},{"url":"https://dashboard.shadowserver.org/statistics/honeypot/vulnerability/map/?day=2024-01-23&host_type=src&vulnerability=cve-2021-32030","date":"2024-01-23"},{"url":"https://dashboard.shadowserver.org/statistics/honeypot/vulnerability/map/?day=2024-01-24&host_type=src&vulnerability=cve-2021-32030","date":"2024-01-24"},{"url":"https://dashboard.shadowserver.org/statistics/honeypot/vulnerability/map/?day=2024-01-27&host_type=src&vulnerability=cve-2021-32030","date":"2024-01-27"},{"url":"https://dashboard.shadowserver.org/statistics/honeypot/vulnerability/map/?day=2024-01-28&host_type=src&vulnerability=cve-2021-32030","date":"2024-01-28"}],"evidenceTotal":997,"provenance":"source"},"exploited":true,"otx":{"pulseCount":50,"pulses":[{"name":"Actively_Exploited_Kev 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2026","url":"https://otx.alienvault.com/pulse/6ad62f63c24a405a3423cc13","created":"2026-10-19"},{"name":"Actively_Exploited_Kev | Oct 19, 2026","url":"https://otx.alienvault.com/pulse/6ad4dda174e5797d0bd238b7","created":"2026-10-18"},{"name":"Actively_Exploited_Kev | Oct 18, 2026","url":"https://otx.alienvault.com/pulse/6ad38c22e1848f8189d1c121","created":"2026-10-17"}],"provenance":"machine"},"cwes":[{"id":"CWE-287","name":"Improper Authentication"}],"references":[{"url":"https://github.com/atredispartners/advisories/blob/master/ATREDIS-2020-0010.md","tags":["Broken Link","Exploit","Third Party 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