Critical severity · published Apr 2, 2021
CVE-2021-1871
Apple iOS, iPadOS, and macOS WebKit Remote Code Execution Vulnerability
In wildKEV
9.8
CVSS
7%
EPSS
Yes
On KEV
Description
A logic issue was addressed with improved restrictions. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave, iOS 14.4 and iPadOS 14.4. A remote attacker may be able to cause arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited..
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)7.0% · higher than 94% of CVEs
Exploited in the wildYes
CISA KEVListed Nov 3, 2021
Federal remediation dueNov 17, 2021
Ransomware campaign useNot known
Affected products
Which versions
MA
macOS · Apple
before 11.2 · source: vendor, NVD
IO
iOS · Apple
before 14.4 · source: NVD
IA
iOS and iPadOS · Apple
before 14.4 · source: vendor
DL
Debian Linux · Debian
10.0 · source: NVD
FE
Fedora · Fedoraproject
33 · source: NVD
MO
Mac OS X · Apple
10.15 before 10.15.7; 10.15.7; 10.15.7; 10.15.7 · source: NVD
II
iOS, iPadOS, and macOS · Apple
All versions, or not specified · source: KEV
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-1871
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-1871
CISA KEV catalogue
https://www.cisa.gov/known-exploited-vulnerabilities-catalog
x_refsource_MISC
https://support.apple.com/en-us/HT212147
x_refsource_MISC
https://support.apple.com/en-us/HT212146
vendor-advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L3L6ZZOU5JS7E3RFYGLP7UFLXCG7TNLU/
vendor-advisory
https://www.debian.org/security/2021/dsa-4923
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