Critical severity · published Sep 8, 2021
CVE-2021-1834
An out-of-bounds write issue was addressed with improved bounds checking
9.8
CVSS
3%
EPSS
No
On KEV
Description
An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in macOS Big Sur 11.3, Security Update 2021-002 Catalina, Security Update 2021-003 Mojave. A malicious application may be able to execute arbitrary code with kernel privileges.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)3.0% · higher than 87% 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 11.3 · source: NVD
MO
Mac OS X · Apple
10.14; 10.14.0; 10.14.1; 10.14.2; 10.14.3; 10.14.4; +34 more · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-1834
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-1834
Vendor Advisory
https://support.apple.com/en-us/HT212325
Vendor Advisory
https://support.apple.com/en-us/HT212326
Vendor Advisory
https://support.apple.com/en-us/HT212327
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