How severe is CVE-2020-3843?

CVE-2020-3843 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-3843 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-3843?

CVE-2020-3843 primarily affects Apple Iphone Os. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-3843?

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-2020-3843 published?

CVE-2020-3843 was published on 2020-02-27 and last updated on 2026-06-17.

CVE-2020-3843

CVE-2020-3843 is a high-severity vulnerability in Apple Iphone Os with a CVSS 3.x base score of 8.8. 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-787.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 9.3
EPSS exploit prediction: 4% (88th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Apple Iphone Os
Published: 2020-02-27
Last modified: 2026-06-17

Description

A memory corruption issue was addressed with improved input validation. This issue is fixed in iOS 12.4.7, watchOS 5.3.7. A remote attacker may be able to cause unexpected system termination or corrupt kernel memory.

Frequently asked questions

What is CVE-2020-3843?: A memory corruption issue was addressed with improved input validation. This issue is fixed in iOS 12.4.7, watchOS 5.3.7. A remote attacker may be able to cause unexpected system termination or corrupt kernel memory.
How severe is CVE-2020-3843?: CVE-2020-3843 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-3843 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-3843?: CVE-2020-3843 primarily affects Apple Iphone Os. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-3843?: 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-2020-3843 published?: CVE-2020-3843 was published on 2020-02-27 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:watchos:*:*:*:*:*:*:*:*

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