How severe is CVE-2026-4254?

CVE-2026-4254 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-4254 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-4254?

CVE-2026-4254 affects Tenda Ac8 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-4254?

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

Does CVE-2026-4254 have an EU (EUVD) identifier?

Yes. CVE-2026-4254 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-12488.

When was CVE-2026-4254 published?

CVE-2026-4254 was published on 2026-03-16 and last updated on 2026-06-17.

CVE-2026-4254

CVE-2026-4254 is a critical-severity vulnerability in Tenda Ac8 Firmware with a CVSS 3.x base score of 9.8. 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-787.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 10.0
CVSS v4: 8.9
EPSS exploit prediction: 1% (55th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-12488
Weakness: CWE-787
Affected product: Tenda Ac8 Firmware
Published: 2026-03-16
Last modified: 2026-06-17

Description

A weakness has been identified in Tenda AC8 up to 16.03.50.11. This vulnerability affects the function doSystemCmd of the file /goform/SysToolChangePwd of the component HTTP Endpoint. This manipulation of the argument local_2c causes stack-based buffer overflow. The attack can be initiated remotely. The exploit has been made available to the public and could be used for attacks.

Frequently asked questions

What is CVE-2026-4254?: A weakness has been identified in Tenda AC8 up to 16.03.50.11. This vulnerability affects the function doSystemCmd of the file /goform/SysToolChangePwd of the component HTTP Endpoint. This manipulation of the argument local_2c causes stack-based buffer overflow. The attack can be initiated remotely. The exploit has been made available to the public and could be used for attacks.
How severe is CVE-2026-4254?: CVE-2026-4254 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-4254 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-4254?: CVE-2026-4254 affects Tenda Ac8 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-4254?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2026-4254 have an EU (EUVD) identifier?: Yes. CVE-2026-4254 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-12488.
When was CVE-2026-4254 published?: CVE-2026-4254 was published on 2026-03-16 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:tenda:ac8_firmware:*:*:*:*:*:*:*:*

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