How severe is CVE-2026-4591?

CVE-2026-4591 has a CVSS 3.x base score of 4.7, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2026-4591 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-4591?

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

Does CVE-2026-4591 have an EU (EUVD) identifier?

Yes. CVE-2026-4591 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-14457.

When was CVE-2026-4591 published?

CVE-2026-4591 was published on 2026-03-23 and last updated on 2026-06-17.

CVE-2026-4591

CVE-2026-4591 is a medium-severity vulnerability with a CVSS 3.x base score of 4.7. 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-77.

Key facts

Severity: Medium (CVSS 3.x base score 4.7)
CVSS v2: 5.8
CVSS v4: 2.0
EPSS exploit prediction: 2% (79th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-14457
Weakness: CWE-77
Published: 2026-03-23
Last modified: 2026-06-17

Description

A weakness has been identified in kalcaddle kodbox 1.64. This affects the function checkBin of the file /workspace/source-code/plugins/fileThumb/app.php of the component fileThumb Endpoint. Executing a manipulation can lead to os command injection. The attack can be executed remotely. The exploit has been made available to the public and could 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-2026-4591?: A weakness has been identified in kalcaddle kodbox 1.64. This affects the function checkBin of the file /workspace/source-code/plugins/fileThumb/app.php of the component fileThumb Endpoint. Executing a manipulation can lead to os command injection. The attack can be executed remotely. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.
How severe is CVE-2026-4591?: CVE-2026-4591 has a CVSS 3.x base score of 4.7, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2026-4591 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-4591?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-4591 have an EU (EUVD) identifier?: Yes. CVE-2026-4591 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-14457.
When was CVE-2026-4591 published?: CVE-2026-4591 was published on 2026-03-23 and last updated on 2026-06-17.

References

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