CVE-2021-3128: High severity ASUS Zenwifi Ax \(xt8\) Firmware vulnerability

Published Apr 12, 2021
·
Updated

In ASUS RT-AX3000, ZenWiFi AX (XT8), RT-AX88U, and other ASUS routers with firmware < 3.0.0.4.386.42095 or < 9.0.0.4.386.41994, when IPv6 is used, a routing loop can occur that generates excessive network traffic between an affected device and its upstream ISP's router. This occurs when a link prefix route points to a point-to-point link, a destination IPv6 address belongs to the prefix and is not a local IPv6 address, and a router advertisement is received with at least one global unique IPv6 prefix for which the on-link flag is set.

Affected Software

189 affected components
ASUS Zenwifi Ax \(xt8\) Firmware<3.0.0.4.386.42095
ASUS Zenwifi Ax \(xt8\)
ASUS Zenwifi Ax \(xt8\) Firmware<9.0.0.4.386.41994
ASUS RT-AX3000 firmware<3.0.0.4.386.42095
ASUS RT-AX3000
ASUS RT-AX3000 firmware<9.0.0.4.386.41994
ASUS Rt-ax55 Firmware<3.0.0.4.386.42095
ASUS RT-AX55
ASUS Rt-ax55 Firmware<9.0.0.4.386.41994
ASUS Rt-ax56u Firmware<3.0.0.4.386.42095
ASUS RT-AX56U
ASUS Rt-ax56u Firmware<9.0.0.4.386.41994
ASUS Rt-ax58u Firmware<3.0.0.4.386.42095
ASUS RT-AX58U
ASUS Rt-ax58u Firmware<9.0.0.4.386.41994
ASUS Rt-ax68u Firmware<3.0.0.4.386.42095
ASUS RT-AX68U
ASUS Rt-ax68u Firmware<9.0.0.4.386.41994
ASUS Rt-ax82u Firmware<3.0.0.4.386.42095
ASUS RT-AX82U
ASUS Rt-ax82u Firmware<9.0.0.4.386.41994
ASUS Rt-ax86u Firmware<3.0.0.4.386.42095
ASUS RT-AX86U
ASUS Rt-ax86u Firmware<9.0.0.4.386.41994
ASUS Rt-ax88u Firmware<3.0.0.4.386.42095
ASUS RT-AX88U
ASUS Rt-ax88u Firmware<9.0.0.4.386.41994
ASUS Rt-ac66u B1 Firmware<3.0.0.4.386.42095
ASUS RT-AC66U B1
ASUS Rt-ac66u B1 Firmware<9.0.0.4.386.41994
ASUS Rt-ac1750 B1 Firmware<3.0.0.4.386.42095
ASUS Rt-ac1750 B1
ASUS Rt-ac1750 B1 Firmware<9.0.0.4.386.41994
ASUS Rt-ac1900 Firmware<3.0.0.4.386.42095
ASUS RT-AC1900
ASUS Rt-ac1900 Firmware<9.0.0.4.386.41994
ASUS Rt-ac1900p Firmware<3.0.0.4.386.42095
ASUS RT-AC1900P
ASUS Rt-ac1900p Firmware<9.0.0.4.386.41994
ASUS Rt-ac1900u Firmware<3.0.0.4.386.42095
ASUS Rt-ac1900u
ASUS Rt-ac1900u Firmware<9.0.0.4.386.41994
ASUS Rt-ac2900 Firmware<3.0.0.4.386.42095
ASUS RT-AC2900
ASUS Rt-ac2900 Firmware<9.0.0.4.386.41994
ASUS Rt-ac3100 Firmware<3.0.0.4.386.42095
ASUS RT-AC3100
ASUS Rt-ac3100 Firmware<9.0.0.4.386.41994
ASUS Rt-ac5300 Firmware<3.0.0.4.386.42095
ASUS RT-AC5300
ASUS Rt-ac5300 Firmware<9.0.0.4.386.41994
ASUS Rt-ac58u Firmware<3.0.0.4.386.42095
ASUS RT-AC58U
ASUS Rt-ac58u Firmware<9.0.0.4.386.41994
ASUS Rt-ac65u Firmware<3.0.0.4.386.42095
ASUS Rt-ac65u
ASUS Rt-ac65u Firmware<9.0.0.4.386.41994
ASUS Rt-ac68p Firmware<3.0.0.4.386.42095
ASUS Rt-ac68p
ASUS Rt-ac68p Firmware<9.0.0.4.386.41994
ASUS Rt-ac68r Firmware<3.0.0.4.386.42095
ASUS RT-AC68R
ASUS Rt-ac68r Firmware<9.0.0.4.386.41994
ASUS Rt-ac68rw Firmware<3.0.0.4.386.42095
ASUS Rt-ac68rw
ASUS Rt-ac68rw Firmware<9.0.0.4.386.41994
ASUS RT-AC68U Firmware<3.0.0.4.386.42095
ASUS RT-AC68U
ASUS RT-AC68U Firmware<9.0.0.4.386.41994
ASUS Rt-ac68w Firmware<3.0.0.4.386.42095
ASUS Rt-ac68w
ASUS Rt-ac68w Firmware<9.0.0.4.386.41994
ASUS Rt-ac85u Firmware<3.0.0.4.386.42095
ASUS Rt-ac85u
ASUS Rt-ac85u Firmware<9.0.0.4.386.41994
ASUS Rt-ac86u Firmware<3.0.0.4.386.42095
ASUS RT-AC86U
ASUS Rt-ac86u Firmware<9.0.0.4.386.41994
ASUS Rt-ac88u Firmware<3.0.0.4.386.42095
ASUS RT-AC88U
ASUS Rt-ac88u Firmware<9.0.0.4.386.41994
All of the following
ASUS Zenwifi Ax \(xt8\) Firmware<3.0.0.4.386.42095
ASUS Zenwifi Ax \(xt8\)
All of the following
ASUS Zenwifi Ax \(xt8\) Firmware<9.0.0.4.386.41994
ASUS Zenwifi Ax \(xt8\)
All of the following
ASUS RT-AX3000 firmware<3.0.0.4.386.42095
ASUS RT-AX3000
All of the following
ASUS RT-AX3000 firmware<9.0.0.4.386.41994
ASUS RT-AX3000
All of the following
ASUS Rt-ax55 Firmware<3.0.0.4.386.42095
ASUS RT-AX55
All of the following
ASUS Rt-ax55 Firmware<9.0.0.4.386.41994
ASUS RT-AX55
All of the following
ASUS Rt-ax56u Firmware<3.0.0.4.386.42095
ASUS RT-AX56U
All of the following
ASUS Rt-ax56u Firmware<9.0.0.4.386.41994
ASUS RT-AX56U
All of the following
ASUS Rt-ax58u Firmware<3.0.0.4.386.42095
ASUS RT-AX58U
All of the following
ASUS Rt-ax58u Firmware<9.0.0.4.386.41994
ASUS RT-AX58U
All of the following
ASUS Rt-ax68u Firmware<3.0.0.4.386.42095
ASUS RT-AX68U
All of the following
ASUS Rt-ax68u Firmware<9.0.0.4.386.41994
ASUS RT-AX68U
All of the following
ASUS Rt-ax82u Firmware<3.0.0.4.386.42095
ASUS RT-AX82U
All of the following
ASUS Rt-ax82u Firmware<9.0.0.4.386.41994
ASUS RT-AX82U
All of the following
ASUS Rt-ax86u Firmware<3.0.0.4.386.42095
ASUS RT-AX86U
All of the following
ASUS Rt-ax86u Firmware<9.0.0.4.386.41994
ASUS RT-AX86U
All of the following
ASUS Rt-ax88u Firmware<3.0.0.4.386.42095
ASUS RT-AX88U
All of the following
ASUS Rt-ax88u Firmware<9.0.0.4.386.41994
ASUS RT-AX88U
All of the following
ASUS Rt-ac66u B1 Firmware<3.0.0.4.386.42095
ASUS RT-AC66U B1
All of the following
ASUS Rt-ac66u B1 Firmware<9.0.0.4.386.41994
ASUS RT-AC66U B1
All of the following
ASUS Rt-ac1750 B1 Firmware<3.0.0.4.386.42095
ASUS Rt-ac1750 B1
All of the following
ASUS Rt-ac1750 B1 Firmware<9.0.0.4.386.41994
ASUS Rt-ac1750 B1
All of the following
ASUS Rt-ac1900 Firmware<3.0.0.4.386.42095
ASUS RT-AC1900
All of the following
ASUS Rt-ac1900 Firmware<9.0.0.4.386.41994
ASUS RT-AC1900
All of the following
ASUS Rt-ac1900p Firmware<3.0.0.4.386.42095
ASUS RT-AC1900P
All of the following
ASUS Rt-ac1900p Firmware<9.0.0.4.386.41994
ASUS RT-AC1900P
All of the following
ASUS Rt-ac1900u Firmware<3.0.0.4.386.42095
ASUS Rt-ac1900u
All of the following
ASUS Rt-ac1900u Firmware<9.0.0.4.386.41994
ASUS Rt-ac1900u
All of the following
ASUS Rt-ac2900 Firmware<3.0.0.4.386.42095
ASUS RT-AC2900
All of the following
ASUS Rt-ac2900 Firmware<9.0.0.4.386.41994
ASUS RT-AC2900
All of the following
ASUS Rt-ac3100 Firmware<3.0.0.4.386.42095
ASUS RT-AC3100
All of the following
ASUS Rt-ac3100 Firmware<9.0.0.4.386.41994
ASUS RT-AC3100
All of the following
ASUS Rt-ac5300 Firmware<3.0.0.4.386.42095
ASUS RT-AC5300
All of the following
ASUS Rt-ac5300 Firmware<9.0.0.4.386.41994
ASUS RT-AC5300
All of the following
ASUS Rt-ac58u Firmware<3.0.0.4.386.42095
ASUS RT-AC58U
All of the following
ASUS Rt-ac58u Firmware<9.0.0.4.386.41994
ASUS RT-AC58U
All of the following
ASUS Rt-ac65u Firmware<3.0.0.4.386.42095
ASUS Rt-ac65u
All of the following
ASUS Rt-ac65u Firmware<9.0.0.4.386.41994
ASUS Rt-ac65u
All of the following
ASUS Rt-ac68p Firmware<3.0.0.4.386.42095
ASUS Rt-ac68p
All of the following
ASUS Rt-ac68p Firmware<9.0.0.4.386.41994
ASUS Rt-ac68p
All of the following
ASUS Rt-ac68r Firmware<3.0.0.4.386.42095
ASUS RT-AC68R
All of the following
ASUS Rt-ac68r Firmware<9.0.0.4.386.41994
ASUS RT-AC68R
All of the following
ASUS Rt-ac68rw Firmware<3.0.0.4.386.42095
ASUS Rt-ac68rw
All of the following
ASUS Rt-ac68rw Firmware<9.0.0.4.386.41994
ASUS Rt-ac68rw
All of the following
ASUS RT-AC68U Firmware<3.0.0.4.386.42095
ASUS RT-AC68U
All of the following
ASUS RT-AC68U Firmware<9.0.0.4.386.41994
ASUS RT-AC68U
All of the following
ASUS Rt-ac68w Firmware<3.0.0.4.386.42095
ASUS Rt-ac68w
All of the following
ASUS Rt-ac68w Firmware<9.0.0.4.386.41994
ASUS Rt-ac68w
All of the following
ASUS Rt-ac85u Firmware<3.0.0.4.386.42095
ASUS Rt-ac85u
All of the following
ASUS Rt-ac85u Firmware<9.0.0.4.386.41994
ASUS Rt-ac85u
All of the following
ASUS Rt-ac86u Firmware<3.0.0.4.386.42095
ASUS RT-AC86U
All of the following
ASUS Rt-ac86u Firmware<9.0.0.4.386.41994
ASUS RT-AC86U
All of the following
ASUS Rt-ac88u Firmware<3.0.0.4.386.42095
ASUS RT-AC88U
All of the following
ASUS Rt-ac88u Firmware<9.0.0.4.386.41994
ASUS RT-AC88U

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade ASUS routers (RT-AX3000, ZenWiFi AX (XT8), RT-AX88U, and others) to a version that resolves this vulnerability.

    Fixed in 3.0.0.4.386.42095
  2. Upgrade

    Upgrade ASUS routers (RT-AX3000, ZenWiFi AX (XT8), RT-AX88U, and others) to a version that resolves this vulnerability.

    Fixed in 9.0.0.4.386.41994

Event History

Apr 12, 2021
CVE Published
via MITRE·05:41 PM
Data Sourced
via MITRE·05:41 PM
Description
Data Sourced
via NVD·07:15 PM
DescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is the severity of CVE-2021-3128?

CVE-2021-3128 is considered a high-severity vulnerability due to the potential for significant network disruption.

2

How do I fix CVE-2021-3128?

To fix CVE-2021-3128, update your ASUS router firmware to versions 3.0.0.4.386.42095 or later, or 9.0.0.4.386.41994 or later.

3

Which ASUS router models are affected by CVE-2021-3128?

CVE-2021-3128 affects various ASUS routers including RT-AX3000, ZenWiFi AX (XT8), and RT-AX88U with outdated firmware.

4

What type of issue does CVE-2021-3128 cause in affected routers?

CVE-2021-3128 can cause a routing loop that leads to excessive network traffic and potential service interruptions.

5

Is CVE-2021-3128 an IPv6 related vulnerability?

Yes, CVE-2021-3128 specifically triggers a vulnerability when IPv6 is used in the affected ASUS routers.

Company

Resources

Contact

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