High severity · published Aug 24, 2021
CVE-2021-30977
A buffer overflow was addressed with improved bounds checking
7.8
CVSS
1.5%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.5% · higher than 74% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MA
macOS · Apple
11.0 before 11.6.2; 12.0 before 12.3 · source: NVD
MO
Mac OS X · Apple
10.15 before 10.15.7; 10.15.7; 10.15.7; 10.15.7; 10.15.7; 10.15.7; +5 more · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-30977
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-30977
support.apple.com
https://support.apple.com/en-us/HT212978
support.apple.com
https://support.apple.com/en-us/HT212979
support.apple.com
https://support.apple.com/en-us/HT212981
support.apple.com
https://support.apple.com/kb/HT213183
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