High severity · published Sep 8, 2021
CVE-2021-1817
A memory corruption issue was addressed with improved state management
8.8
CVSS
1.9%
EPSS
No
On KEV
Description
A memory corruption issue was addressed with improved state management. This issue is fixed in macOS Big Sur 11.3, iOS 14.5 and iPadOS 14.5, watchOS 7.4, tvOS 14.5. Processing maliciously crafted web content may lead to arbitrary code execution.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.9% · higher than 80% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
IO
iOS · Apple
before 14.5 · source: NVD
MA
macOS · Apple
11.0 before 11.3 · source: NVD
TV
Tvos · Apple
before 14.5 · source: NVD
WA
Watchos · Apple
before 7.4 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-1817
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-1817
Vendor Advisory
https://support.apple.com/en-us/HT212317
Vendor Advisory
https://support.apple.com/en-us/HT212323
Vendor Advisory
https://support.apple.com/en-us/HT212324
Vendor Advisory
https://support.apple.com/en-us/HT212325
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