How severe is CVE-2016-4721?

CVE-2016-4721 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2016-4721 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (58th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-4721?

CVE-2016-4721 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-2016-4721?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2016-4721 published?

CVE-2016-4721 was published on 2017-02-20 and last updated on 2026-06-17.

CVE-2016-4721

CVE-2016-4721 is a medium-severity vulnerability in Apple Iphone Os with a CVSS 3.x base score of 5.9. 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-254.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
CVSS v2: 4.3
EPSS exploit prediction: 1% (58th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-254
Affected product: Apple Iphone Os
Published: 2017-02-20
Last modified: 2026-06-17

Description

An issue was discovered in certain Apple products. iOS before 10.1 is affected. macOS before 10.12.1 is affected. The issue involves the "IDS - Connectivity" component, which allows man-in-the-middle attackers to spoof calls via a "switch caller" notification.

Frequently asked questions

What is CVE-2016-4721?: An issue was discovered in certain Apple products. iOS before 10.1 is affected. macOS before 10.12.1 is affected. The issue involves the "IDS - Connectivity" component, which allows man-in-the-middle attackers to spoof calls via a "switch caller" notification.
How severe is CVE-2016-4721?: CVE-2016-4721 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2016-4721 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (58th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-4721?: CVE-2016-4721 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-2016-4721?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2016-4721 published?: CVE-2016-4721 was published on 2017-02-20 and last updated on 2026-06-17.

References

Affected products (2)

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

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