How severe is CVE-2021-44158?

CVE-2021-44158 has a CVSS 3.x base score of 8.0, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-44158 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-44158?

CVE-2021-44158 affects Asus Rt-ax56u Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-44158?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-44158 published?

CVE-2021-44158 was published on 2022-01-03 and last updated on 2026-06-17.

CVE-2021-44158

CVE-2021-44158 is a high-severity vulnerability in Asus Rt-ax56u Firmware with a CVSS 3.x base score of 8.0. 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-1284.

Key facts

Severity: High (CVSS 3.x base score 8.0)
CVSS v2: 7.7
EPSS exploit prediction: 1% (48th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-1284
Affected product: Asus Rt-ax56u Firmware
Published: 2022-01-03
Last modified: 2026-06-17

Description

ASUS RT-AX56U Wi-Fi Router is vulnerable to stack-based buffer overflow due to improper validation for httpd parameter length. An authenticated local area network attacker can launch arbitrary code execution to control the system or disrupt service.

Frequently asked questions

What is CVE-2021-44158?: ASUS RT-AX56U Wi-Fi Router is vulnerable to stack-based buffer overflow due to improper validation for httpd parameter length. An authenticated local area network attacker can launch arbitrary code execution to control the system or disrupt service.
How severe is CVE-2021-44158?: CVE-2021-44158 has a CVSS 3.x base score of 8.0, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-44158 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-44158?: CVE-2021-44158 affects Asus Rt-ax56u Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-44158?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-44158 published?: CVE-2021-44158 was published on 2022-01-03 and last updated on 2026-06-17.

References

https://www.twcert.org.tw/tw/cp-132-5431-d23be-1.html

Affected products (1)

cpe:2.3:o:asus:rt-ax56u_firmware:3.0.0.4.386.44266:*:*:*:*:*:*:*

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