Critical severity · published Apr 2, 2021
CVE-2021-1796
An out-of-bounds write was addressed with improved input validation
9.8
CVSS
2%
EPSS
No
On KEV
Description
An out-of-bounds write was addressed with improved input validation. This issue is fixed in iOS 14.4 and iPadOS 14.4. A remote attacker may be able to cause arbitrary code execution.
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)2.0% · higher than 81% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
IO
iOS · Apple
before 14.4 · source: NVD
IO
Ipad OS · Apple
before 14.4 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-1796
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-1796
Vendor Advisory
https://support.apple.com/en-us/HT212146
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