How severe is CVE-2026-9421?

CVE-2026-9421 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2026-9421 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-9421?

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-2026-9421 have an EU (EUVD) identifier?

Yes. CVE-2026-9421 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31624.

When was CVE-2026-9421 published?

CVE-2026-9421 was published on 2026-05-25 and last updated on 2026-06-17.

CVE-2026-9421

CVE-2026-9421 is a high-severity vulnerability with a CVSS 3.x base score of 7.3. 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-284.

Key facts

Severity: High (CVSS 3.x base score 7.3)
CVSS v2: 7.5
CVSS v4: 5.5
EPSS exploit prediction: 0% (21st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-31624
Weakness: CWE-284
Published: 2026-05-25
Last modified: 2026-06-17

Description

A vulnerability was determined in KLiK SocialMediaWebsite 1.0. This vulnerability affects the function uniqid of the file upload.inc.php of the component File Handler. This manipulation causes unrestricted upload. The attack can be initiated remotely. The exploit has been publicly disclosed and may be utilized.

Frequently asked questions

What is CVE-2026-9421?: A vulnerability was determined in KLiK SocialMediaWebsite 1.0. This vulnerability affects the function uniqid of the file upload.inc.php of the component File Handler. This manipulation causes unrestricted upload. The attack can be initiated remotely. The exploit has been publicly disclosed and may be utilized.
How severe is CVE-2026-9421?: CVE-2026-9421 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2026-9421 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-9421?: 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-2026-9421 have an EU (EUVD) identifier?: Yes. CVE-2026-9421 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31624.
When was CVE-2026-9421 published?: CVE-2026-9421 was published on 2026-05-25 and last updated on 2026-06-17.

References

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