How severe is CVE-2026-4042?

CVE-2026-4042 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-4042 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-4042?

CVE-2026-4042 affects Tenda I12 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-4042?

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.

Does CVE-2026-4042 have an EU (EUVD) identifier?

Yes. CVE-2026-4042 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-11589.

When was CVE-2026-4042 published?

CVE-2026-4042 was published on 2026-03-12 and last updated on 2026-06-17.

CVE-2026-4042

CVE-2026-4042 is a high-severity vulnerability in Tenda I12 Firmware with a CVSS 3.x base score of 8.8. 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: High (CVSS 3.x base score 8.8)
CVSS v2: 9.0
CVSS v4: 7.4
EPSS exploit prediction: 1% (52nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-11589
Weakness: CWE-787
Affected product: Tenda I12 Firmware
Published: 2026-03-12
Last modified: 2026-06-17

Description

A weakness has been identified in Tenda i12 1.0.0.6(2204). The affected element is the function formWifiMacFilterGet of the file /goform/WifiMacFilterGet. This manipulation of the argument index causes stack-based buffer overflow. The attack may be initiated remotely. The exploit has been made available to the public and could be used for attacks.

Frequently asked questions

What is CVE-2026-4042?: A weakness has been identified in Tenda i12 1.0.0.6(2204). The affected element is the function formWifiMacFilterGet of the file /goform/WifiMacFilterGet. This manipulation of the argument index causes stack-based buffer overflow. The attack may be initiated remotely. The exploit has been made available to the public and could be used for attacks.
How severe is CVE-2026-4042?: CVE-2026-4042 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-4042 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-4042?: CVE-2026-4042 affects Tenda I12 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-4042?: 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.
Does CVE-2026-4042 have an EU (EUVD) identifier?: Yes. CVE-2026-4042 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-11589.
When was CVE-2026-4042 published?: CVE-2026-4042 was published on 2026-03-12 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:tenda:i12_firmware:1.0.0.6\(2204\):*:*:*:*:*:*:*

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