CVE-2021-41435
CVE-2021-41435 is a critical-severity vulnerability in Asus Gt-ax11000 Firmware with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-307.
Key facts
- Severity: Critical (CVSS 3.x base score 9.8)
- CVSS v2: 10.0
- EPSS exploit prediction: 6% (92nd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-307
- Affected product: Asus Gt-ax11000 Firmware
- Published:
- Last modified:
Description
A brute-force protection bypass in CAPTCHA protection in ASUS ROG Rapture GT-AX11000, RT-AX3000, RT-AX55, RT-AX56U, RT-AX56U_V2, RT-AX58U, RT-AX82U, RT-AX82U GUNDAM EDITION, RT-AX86 Series(RT-AX86U/RT-AX86S), RT-AX86U ZAKU II EDITION, RT-AX88U, RT-AX92U, TUF Gaming AX3000, TUF Gaming AX5400 (TUF-AX5400), ASUS ZenWiFi XD6, ASUS ZenWiFi AX (XT8) before 3.0.0.4.386.45898, and RT-AX68U before 3.0.0.4.386.45911, allows a remote attacker to attempt any number of login attempts via sending a specific HTTP request.
Frequently asked questions
- What is CVE-2021-41435?
- A brute-force protection bypass in CAPTCHA protection in ASUS ROG Rapture GT-AX11000, RT-AX3000, RT-AX55, RT-AX56U, RT-AX56U_V2, RT-AX58U, RT-AX82U, RT-AX82U GUNDAM EDITION, RT-AX86 Series(RT-AX86U/RT-AX86S), RT-AX86U ZAKU II EDITION, RT-AX88U, RT-AX92U, TUF Gaming AX3000, TUF Gaming AX5400 (TUF-AX5400), ASUS ZenWiFi XD6, ASUS ZenWiFi AX (XT8) before 3.0.0.4.386.45898, and RT-AX68U before 3.0.0.4.386.45911, allows a remote attacker to attempt any number of login attempts via sending a specific HTTP request.
- How severe is CVE-2021-41435?
- CVE-2021-41435 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-41435 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-41435?
- CVE-2021-41435 primarily affects Asus Gt-ax11000 Firmware. In total, 18 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-41435?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2021-41435 published?
- CVE-2021-41435 was published on 2021-11-19 and last updated on 2026-07-05.
References
- https://rog.asus.com/networking/rog-rapture-gt-ax11000-model/helpdesk_bios
- https://www.asus.com/Networking-IoT-Servers/Whole-Home-Mesh-WiFi-System/ZenWiFi-WiFi-Systems/ASUS-ZenWiFi-AX-XT8-/HelpDesk_BIOS/
- https://www.asus.com/Networking-IoT-Servers/Whole-Home-Mesh-WiFi-System/ZenWiFi-WiFi-Systems/ASUS-ZenWiFi-XD6/HelpDesk_BIOS/
- https://www.asus.com/Networking-IoT-Servers/WiFi-Routers/ASUS-WiFi-Routers/RT-AX3000/HelpDesk_BIOS/
- https://www.asus.com/Networking-IoT-Servers/WiFi-Routers/ASUS-WiFi-Routers/RT-AX56U/HelpDesk_BIOS/
- https://www.asus.com/Networking-IoT-Servers/WiFi-Routers/ASUS-WiFi-Routers/RT-AX68U/HelpDesk_BIOS/
- https://www.asus.com/Networking-IoT-Servers/WiFi-Routers/All-series/RT-AX55/HelpDesk_BIOS/
- http://asus.com
Affected products (18)
- cpe:2.3:o:asus:gt-ax11000_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:asus:rt-ax3000_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:asus:rt-ax55_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:asus:rt-ax56u_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:asus:rt-ax56u_v2_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:asus:rt-ax58u_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:asus:rt-ax82u_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:asus:rt-ax82u_gundam_edition_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:asus:rt-ax86u_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:asus:rt-ax86s_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:asus:rt-ax86u_zaku_ii_edition_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:asus:rt-ax88u_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:asus:rt-ax92u_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:asus:tuf_gaming_ax3000_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:asus:tuf-ax5400_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:asus:zenwifi_xd6_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:asus:zenwifi_ax_\(xt8\)_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:asus:rt-ax68u_firmware:*:*:*:*:*:*:*:*
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