How severe is CVE-2021-30836?

CVE-2021-30836 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-30836 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-30836?

CVE-2021-30836 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-2021-30836?

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

When was CVE-2021-30836 published?

CVE-2021-30836 was published on 2021-10-28 and last updated on 2026-06-17.

CVE-2021-30836

CVE-2021-30836 is a medium-severity vulnerability in Apple Safari with a CVSS 3.x base score of 5.5. 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-125.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v2: 4.3
EPSS exploit prediction: 1% (60th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-125
Affected product: Apple Safari
Published: 2021-10-28
Last modified: 2026-06-17

Description

An out-of-bounds read was addressed with improved input validation. This issue is fixed in iOS 14.8 and iPadOS 14.8, tvOS 15, watchOS 8, iOS 15 and iPadOS 15. Processing a maliciously crafted audio file may disclose restricted memory.

Frequently asked questions

What is CVE-2021-30836?: An out-of-bounds read was addressed with improved input validation. This issue is fixed in iOS 14.8 and iPadOS 14.8, tvOS 15, watchOS 8, iOS 15 and iPadOS 15. Processing a maliciously crafted audio file may disclose restricted memory.
How severe is CVE-2021-30836?: CVE-2021-30836 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-30836 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-30836?: CVE-2021-30836 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-2021-30836?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-30836 published?: CVE-2021-30836 was published on 2021-10-28 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-125 (Out-of-bounds Read) vulnerabilities

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