How severe is CVE-2021-40546?

CVE-2021-40546 has a CVSS 3.x base score of 4.9, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-40546 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-40546?

CVE-2021-40546 affects Tenda Ac6 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-40546?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-40546 published?

CVE-2021-40546 was published on 2023-09-05 and last updated on 2026-06-17.

CVE-2021-40546

CVE-2021-40546 is a medium-severity vulnerability in Tenda Ac6 Firmware with a CVSS 3.x base score of 4.9. 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-404.

Key facts

Severity: Medium (CVSS 3.x base score 4.9)
EPSS exploit prediction: 1% (50th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-404
Affected product: Tenda Ac6 Firmware
Published: 2023-09-05
Last modified: 2026-06-17

Description

Tenda AC6 US_AC6V4.0RTL_V02.03.01.26_cn.bin allows attackers (who have the administrator password) to cause a denial of service (device crash) via a long string in the wifiPwd_5G parameter to /goform/setWifi.

Frequently asked questions

What is CVE-2021-40546?: Tenda AC6 US_AC6V4.0RTL_V02.03.01.26_cn.bin allows attackers (who have the administrator password) to cause a denial of service (device crash) via a long string in the wifiPwd_5G parameter to /goform/setWifi.
How severe is CVE-2021-40546?: CVE-2021-40546 has a CVSS 3.x base score of 4.9, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-40546 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-40546?: CVE-2021-40546 affects Tenda Ac6 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-40546?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-40546 published?: CVE-2021-40546 was published on 2023-09-05 and last updated on 2026-06-17.

References

https://github.com/doudoudedi/buffer_overflow/blob/main/Tenda%20AC6%20V4.0-Denial%20of%20Service%20Vulnerability.md

Affected products (1)

cpe:2.3:o:tenda:ac6_firmware:02.03.01.26:*:*:*:*:*:*:*

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