CVE-2021-30977

highpriority · track · 32EPSS 0.015 · 74 %ileDEEUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

1.51% (74th) EPSS

CVSS 9.3 · high

Is it mine?

12 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · cert_bund · nvd

EPSS · scored 2026-10-27

A buffer overflow was addressed with improved bounds checking. This issue is fixed in macOS Monterey 12.1, Security Update 2021-008 Catalina, macOS Big Sur 11.6.2. A malicious application may be able to execute arbitrary code with kernel privileges.

cvss

Technical severity, 0–10. One row per scoring source.

9.3

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.09.3highAV:N/AC:M/Au:N/C:C/I:C/A:Cprimary · NVD / NIST USexploitability 8.6 · impact 10

v3.17.8highCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 1.8 · impact 5.9

v3.17.1highCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-120USprimary

affected products (12)

Products and version ranges known to be affected.

Apple macOS Big Sur <11.6.2all versionscert_bundDE
Apple macOS Catalinaall versionscert_bundDEcpe:/o:apple:mac_os:catalina
Apple macOS Monterey <12.1all versionscert_bundDE
Apple macOS≤ Big Sur <11.6.2cert_bundDE
Apple macOS≤ Monterey <12.1cert_bundDE
Apple macOSunspecified → 11.6enisa_euvdEU
Apple macOSunspecified → 12.1enisa_euvdEU
Apple macOSunspecified → 2021enisa_euvdEU
apple mac os x10.15 → 10.15.7nvdUScpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*
apple mac os x= 10.15.7nvdUScpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*
apple macos11.0 → 11.6.2nvdUScpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*
apple macos12.0 → 12.3nvdUScpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2026-0631Apple macOS: Mehrere SchwachstellenDeutsch2021-12-13csaf · cert_bundDE
Ein entfernter, anonymer oder lokaler Angreifer kann mehrere Schwachstellen in Apple macOS ausnutzen, um beliebigen Programmcode auszuführen, beliebigen Programmcode mit Kernel-Privilegien auszuführen, seine Privilegien zu erweitern, vertrauliche Informationen offenzulegen, einen Denial-of-Service-Zustand zu verursachen und Sicherheitsmaßnahmen zu umgehen.

also known as (2)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cert_bund nvd NVD CVE.org MITRE

published 2021-08-24modified 2026-06-17

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+5663 more

references (18)

External citations — patches, advisories, analysis.

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