What is CVE-2021-41436?

CVE-2021-41436 is a high-severity vulnerability in ASUS Gt-Ax11000, classified under Inconsistent Interpretation of HTTP Requests (HTTP Request/Response Smuggling). CVSS score: 7.5/10. Published 2021-11-19.

How severe is CVE-2021-41436?

High severity. CVSS v3 base score is 7.5 out of 10.

Is CVE-2021-41436 known to be exploited?

3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Vulnerability in ASUS Gt-Ax11000

CVE-2021-41436

An HTTP request smuggling in web application 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 unauthenticated attacker to DoS via sending a specially crafted HTTP packet.

Vulnerability class: HTTP Request Smuggling

Published 2021-11-19 · last modified 2026-07-09.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.050 (92.1th percentile), scored 2026-10-20.

Low probability of exploitation in the next 30 days, but still tracked. 92nd percentile — 92.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.050 · newest: 0.050 · change: 0.000

Affected products

Weakness classification (CWE)

CWE-444 — Inconsistent Interpretation of HTTP Requests (HTTP Request/Response Smuggling)

Public proof-of-concept exploits

References

af854a3a-2127-422b-91ae-364da2661108 (Vendor Advisory)
www.asus.com/Networking-IoT-Servers/Whole-Home-Mesh-WiFi-System/ZenWiFi-WiFi-Sy… (Product, Vendor Advisory)
rog.asus.com/networking/rog-rapture-gt-ax11000-model/helpdesk_bios (Product, Vendor Advisory)
www.asus.com/Networking-IoT-Servers/WiFi-Routers/ASUS-WiFi-Routers/RT-AX3000/He… (Product, Vendor Advisory)
www.asus.com/Networking-IoT-Servers/WiFi-Routers/All-series/RT-AX55/HelpDesk_BI… (Product, Vendor Advisory)
www.asus.com/Networking-IoT-Servers/WiFi-Routers/ASUS-WiFi-Routers/RT-AX56U/Hel… (Product, Vendor Advisory)
www.asus.com/Networking-IoT-Servers/WiFi-Routers/ASUS-WiFi-Routers/RT-AX68U/Hel… (Product, Vendor Advisory)
www.asus.com/Networking-IoT-Servers/Whole-Home-Mesh-WiFi-System/ZenWiFi-WiFi-Sy… (Product, Vendor Advisory)

Frequently asked questions

What is CVE-2021-41436?: CVE-2021-41436 is a high-severity vulnerability in ASUS Gt-Ax11000, classified under Inconsistent Interpretation of HTTP Requests (HTTP Request/Response Smuggling). CVSS score: 7.5/10. Published 2021-11-19.
How severe is CVE-2021-41436?: High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2021-41436 known to be exploited?: 3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.