How severe is CVE-2018-4398?

CVE-2018-4398 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2018-4398 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-4398?

CVE-2018-4398 primarily affects Apple Iphone Os. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-4398?

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-2018-4398 published?

CVE-2018-4398 was published on 2019-04-03 and last updated on 2026-06-17.

CVE-2018-4398

CVE-2018-4398 is a high-severity vulnerability in Apple Iphone Os with a CVSS 3.x base score of 7.5. 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-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 2% (73rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Apple Iphone Os
Published: 2019-04-03
Last modified: 2026-06-17

Description

An issue existed in the method for determining prime numbers. This issue was addressed by using pseudorandom bases for testing of primes. This issue affected versions prior to iOS 12.1, macOS Mojave 10.14.1, tvOS 12.1, watchOS 5.1, iTunes 12.9.1, iCloud for Windows 7.8.

Frequently asked questions

What is CVE-2018-4398?: An issue existed in the method for determining prime numbers. This issue was addressed by using pseudorandom bases for testing of primes. This issue affected versions prior to iOS 12.1, macOS Mojave 10.14.1, tvOS 12.1, watchOS 5.1, iTunes 12.9.1, iCloud for Windows 7.8.
How severe is CVE-2018-4398?: CVE-2018-4398 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2018-4398 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-4398?: CVE-2018-4398 primarily affects Apple Iphone Os. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-4398?: 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-2018-4398 published?: CVE-2018-4398 was published on 2019-04-03 and last updated on 2026-06-17.

References

Affected products (6)

cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:tvos:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:watchos:*:*:*:*:*:*:*:*
cpe:2.3:a:apple:icloud:*:*:*:*:*:*:*:*
cpe:2.3:a:apple:itunes:*:*:*:*:*:*:*:*

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