How severe is CVE-2024-42220?

CVE-2024-42220 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2024-42220 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-42220?

CVE-2024-42220 affects Microsoft Outlook. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2024-42220?

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-2024-42220 have an EU (EUVD) identifier?

Yes. CVE-2024-42220 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-40005.

When was CVE-2024-42220 published?

CVE-2024-42220 was published on 2024-12-18 and last updated on 2026-06-17.

CVE-2024-42220

CVE-2024-42220 is a high-severity vulnerability in Microsoft Outlook with a CVSS 3.x base score of 7.1. 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-347.

Key facts

Severity: High (CVSS 3.x base score 7.1)
EPSS exploit prediction: 1% (50th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-40005
Weakness: CWE-347
Affected product: Microsoft Outlook
Published: 2024-12-18
Last modified: 2026-06-17

Description

A library injection vulnerability exists in Microsoft Outlook 16.83.3 for macOS. A specially crafted library can leverage Outlook's access privileges, leading to a permission bypass. A malicious application could inject a library and start the program to trigger this vulnerability and then make use of the vulnerable application's permissions.

Frequently asked questions

What is CVE-2024-42220?: A library injection vulnerability exists in Microsoft Outlook 16.83.3 for macOS. A specially crafted library can leverage Outlook's access privileges, leading to a permission bypass. A malicious application could inject a library and start the program to trigger this vulnerability and then make use of the vulnerable application's permissions.
How severe is CVE-2024-42220?: CVE-2024-42220 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2024-42220 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-42220?: CVE-2024-42220 affects Microsoft Outlook. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2024-42220?: 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-2024-42220 have an EU (EUVD) identifier?: Yes. CVE-2024-42220 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-40005.
When was CVE-2024-42220 published?: CVE-2024-42220 was published on 2024-12-18 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:microsoft:outlook:16.83.3:*:*:*:*:macos:*:*

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