CVE & CISA-KEV Catalog

CVE-2021-3128

HIGHEPSS 80th pctl
7.5
CVSS v3
NVD

Description

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.

CWE-834

How to fix

Remediation Available
rt-ac1750 b1 firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
rt-ac1900 firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
rt-ac1900p firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
rt-ac1900u firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
rt-ac2900 firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
rt-ac3100 firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
rt-ac5300 firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
rt-ac58u firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
rt-ac65u firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
rt-ac66u b1 firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
rt-ac68p firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
rt-ac68r firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
rt-ac68rw firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
rt-ac68u firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
rt-ac68w firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
rt-ac85u firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
rt-ac86u firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
rt-ac88u firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
rt-ax3000 firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
rt-ax55 firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
rt-ax56u firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
rt-ax58u firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
rt-ax68u firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
rt-ax82u firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
rt-ax86u firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
rt-ax88u firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD
zenwifi ax \(xt8\) firmwareNVD
Affected:< 9.0.0.4.386.41994Fixed in:9.0.0.4.386.41994CVE-2021-3128derived from NVD

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionNone
ScopeUnchanged

Impact

ConfidentialityNone
IntegrityNone
AvailabilityHigh

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Exploit Intelligence

2.18%probability of exploitation in 30 days
80thpercentile

Elevated risk: more likely to be exploited than 80% of all known CVEs.

References

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2024-11-21.