How severe is CVE-2021-30959?

CVE-2021-30959 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-2021-30959 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-30959?

CVE-2021-30959 primarily affects Apple Mac Os X. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-30959?

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

When was CVE-2021-30959 published?

CVE-2021-30959 was published on 2021-08-24 and last updated on 2026-06-17.

CVE-2021-30959

CVE-2021-30959 is a medium-severity vulnerability in Apple Mac Os X 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-120.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v2: 4.3
EPSS exploit prediction: 1% (53rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-120
Affected product: Apple Mac Os X
Published: 2021-08-24
Last modified: 2026-06-17

Description

A buffer overflow issue was addressed with improved memory handling. This issue is fixed in Security Update 2021-008 Catalina, macOS Big Sur 11.6.2. Parsing a maliciously crafted audio file may lead to disclosure of user information.

Frequently asked questions

What is CVE-2021-30959?: A buffer overflow issue was addressed with improved memory handling. This issue is fixed in Security Update 2021-008 Catalina, macOS Big Sur 11.6.2. Parsing a maliciously crafted audio file may lead to disclosure of user information.
How severe is CVE-2021-30959?: CVE-2021-30959 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-2021-30959 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-30959?: CVE-2021-30959 primarily affects Apple Mac Os X. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-30959?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-30959 published?: CVE-2021-30959 was published on 2021-08-24 and last updated on 2026-06-17.

References

Affected products (10)

cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:security_update_2020-001:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:security_update_2021-001:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:security_update_2021-002:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:security_update_2021-003:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:security_update_2021-004:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:security_update_2021-005:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:security_update_2021-006:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:security_update_2021-007:*:*:*:*:*:*
cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*

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