How severe is CVE-2021-30720?

CVE-2021-30720 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-30720 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-30720?

CVE-2021-30720 primarily affects Apple Safari. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-30720?

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

When was CVE-2021-30720 published?

CVE-2021-30720 was published on 2021-09-08 and last updated on 2026-06-17.

CVE-2021-30720

CVE-2021-30720 is a medium-severity vulnerability in Apple Safari with a CVSS 3.x base score of 5.4. 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-287.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
CVSS v2: 5.8
EPSS exploit prediction: 1% (67th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Apple Safari
Published: 2021-09-08
Last modified: 2026-06-17

Description

A logic issue was addressed with improved restrictions. This issue is fixed in tvOS 14.6, iOS 14.6 and iPadOS 14.6, Safari 14.1.1, macOS Big Sur 11.4, watchOS 7.5. A malicious website may be able to access restricted ports on arbitrary servers.

Frequently asked questions

What is CVE-2021-30720?: A logic issue was addressed with improved restrictions. This issue is fixed in tvOS 14.6, iOS 14.6 and iPadOS 14.6, Safari 14.1.1, macOS Big Sur 11.4, watchOS 7.5. A malicious website may be able to access restricted ports on arbitrary servers.
How severe is CVE-2021-30720?: CVE-2021-30720 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-30720 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-30720?: CVE-2021-30720 primarily affects Apple Safari. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-30720?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-30720 published?: CVE-2021-30720 was published on 2021-09-08 and last updated on 2026-06-17.

References

Affected products (6)

cpe:2.3:a:apple:safari:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:ipados:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:tvos:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:watchos:*:*:*:*:*:*:*:*

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Other CWE-287 (Improper Authentication) vulnerabilities

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