How severe is CVE-2016-4591?

CVE-2016-4591 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 high, integrity none, and availability none.

Is CVE-2016-4591 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-4591?

CVE-2016-4591 affects Apple Webkit. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2016-4591?

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-2016-4591 published?

CVE-2016-4591 was published on 2016-07-22 and last updated on 2026-06-17.

CVE-2016-4591

CVE-2016-4591 is a high-severity vulnerability in Apple Webkit 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-284.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 7.8
EPSS exploit prediction: 4% (90th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-284
Affected product: Apple Webkit
Published: 2016-07-22
Last modified: 2026-06-17

Description

WebKit in Apple iOS before 9.3.3, Safari before 9.1.2, and tvOS before 9.2.2 mishandles the location variable, which allows remote attackers to access the local filesystem via unspecified vectors.

Frequently asked questions

What is CVE-2016-4591?: WebKit in Apple iOS before 9.3.3, Safari before 9.1.2, and tvOS before 9.2.2 mishandles the location variable, which allows remote attackers to access the local filesystem via unspecified vectors.
How severe is CVE-2016-4591?: CVE-2016-4591 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 high, integrity none, and availability none.
Is CVE-2016-4591 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-4591?: CVE-2016-4591 affects Apple Webkit. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2016-4591?: 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-2016-4591 published?: CVE-2016-4591 was published on 2016-07-22 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:apple:webkit:*:*:*:*:*:*:*:*

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