How severe is CVE-2026-5042?

CVE-2026-5042 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-2026-5042 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-2026-5042?

CVE-2026-5042 affects Belkin F9k1122 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-5042?

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-2026-5042 have an EU (EUVD) identifier?

Yes. CVE-2026-5042 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-16987.

When was CVE-2026-5042 published?

CVE-2026-5042 was published on 2026-03-29 and last updated on 2026-06-17.

CVE-2026-5042

CVE-2026-5042 is a high-severity vulnerability in Belkin F9k1122 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% (48th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-16987
Weakness: CWE-787
Affected product: Belkin F9k1122 Firmware
Published: 2026-03-29
Last modified: 2026-06-17

Description

A security flaw has been discovered in Belkin F9K1122 1.00.33. The affected element is the function formCrossBandSwitch of the file /goform/formCrossBandSwitch of the component Parameter Handler. The manipulation of the argument webpage results in stack-based buffer overflow. The attack may be launched remotely. The exploit has been released to the public and may be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.

Frequently asked questions

What is CVE-2026-5042?: A security flaw has been discovered in Belkin F9K1122 1.00.33. The affected element is the function formCrossBandSwitch of the file /goform/formCrossBandSwitch of the component Parameter Handler. The manipulation of the argument webpage results in stack-based buffer overflow. The attack may be launched remotely. The exploit has been released to the public and may be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.
How severe is CVE-2026-5042?: CVE-2026-5042 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-2026-5042 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-2026-5042?: CVE-2026-5042 affects Belkin F9k1122 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-5042?: 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-2026-5042 have an EU (EUVD) identifier?: Yes. CVE-2026-5042 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-16987.
When was CVE-2026-5042 published?: CVE-2026-5042 was published on 2026-03-29 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:belkin:f9k1122_firmware:1.00.33:*:*:*:*:*:*:*

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