How severe is CVE-2024-56156?

CVE-2024-56156 has a CVSS 3.x base score of 9.0, rated critical severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2024-56156 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-56156?

CVE-2024-56156 affects Halo. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2024-56156?

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-2024-56156 have an EU (EUVD) identifier?

Yes. CVE-2024-56156 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-54441.

When was CVE-2024-56156 published?

CVE-2024-56156 was published on 2025-04-25 and last updated on 2026-06-17.

CVE-2024-56156

CVE-2024-56156 is a critical-severity vulnerability in Halo with a CVSS 3.x base score of 9.0. 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-79.

Key facts

Severity: Critical (CVSS 3.x base score 9.0)
CVSS v4: 5.5
EPSS exploit prediction: 1% (46th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-54441
Weakness: CWE-79
Affected product: Halo
Published: 2025-04-25
Last modified: 2026-06-17

Description

Halo is an open source website building tool. Prior to version 2.20.13, a vulnerability in Halo allows attackers to bypass file type validation controls. This bypass enables the upload of malicious files including executables and HTML files, which can lead to stored cross-site scripting attacks and potential remote code execution under certain circumstances. This issue has been patched in version 2.20.13.

Frequently asked questions

What is CVE-2024-56156?: Halo is an open source website building tool. Prior to version 2.20.13, a vulnerability in Halo allows attackers to bypass file type validation controls. This bypass enables the upload of malicious files including executables and HTML files, which can lead to stored cross-site scripting attacks and potential remote code execution under certain circumstances. This issue has been patched in version 2.20.13.
How severe is CVE-2024-56156?: CVE-2024-56156 has a CVSS 3.x base score of 9.0, rated critical severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2024-56156 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-56156?: CVE-2024-56156 affects Halo. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2024-56156?: 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-2024-56156 have an EU (EUVD) identifier?: Yes. CVE-2024-56156 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-54441.
When was CVE-2024-56156 published?: CVE-2024-56156 was published on 2025-04-25 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:halo:halo:*:*:*:*:*:*:*:*

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