How severe is CVE-2019-8555?

CVE-2019-8555 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2019-8555 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-8555?

CVE-2019-8555 affects Apple Mac Os X. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2019-8555?

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.

When was CVE-2019-8555 published?

CVE-2019-8555 was published on 2019-12-18 and last updated on 2026-06-17.

CVE-2019-8555

CVE-2019-8555 is a high-severity vulnerability in Apple Mac Os X with a CVSS 3.x base score of 7.8. 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-119.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 9.3
EPSS exploit prediction: 1% (68th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-119
Affected product: Apple Mac Os X
Published: 2019-12-18
Last modified: 2026-06-17

Description

A buffer overflow was addressed with improved size validation. This issue is fixed in macOS Mojave 10.14.4. A malicious application may be able to execute arbitrary code with kernel privileges.

Frequently asked questions

What is CVE-2019-8555?: A buffer overflow was addressed with improved size validation. This issue is fixed in macOS Mojave 10.14.4. A malicious application may be able to execute arbitrary code with kernel privileges.
How severe is CVE-2019-8555?: CVE-2019-8555 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2019-8555 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-8555?: CVE-2019-8555 affects Apple Mac Os X. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2019-8555?: 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.
When was CVE-2019-8555 published?: CVE-2019-8555 was published on 2019-12-18 and last updated on 2026-06-17.

References

https://support.apple.com/HT209600

Affected products (1)

cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*

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