Medium severity · published Apr 2, 2021
CVE-2021-1879
Apple iOS, iPadOS, and watchOS WebKit Cross-Site Scripting (XSS) Vulnerability
In wildKEV
6.1
CVSS
7.1%
EPSS
Yes
On KEV
Description
This issue was addressed by improved management of object lifetimes. This issue is fixed in iOS 12.5.2, iOS 14.4.2 and iPadOS 14.4.2, watchOS 7.3.3. Processing maliciously crafted web content may lead to universal cross site scripting. 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:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)7.1% · 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
IO
iOS · Apple
before 12.5 · source: vendor, NVD
IA
iOS and iPadOS · Apple
before 14.4 · source: vendor
WA
watchOS · Apple
before 7.3 · source: vendor, NVD
II
iOS, iPadOS, and watchOS · Apple
All versions, or not specified · source: KEV
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-1879
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-1879
CISA KEV catalogue
https://www.cisa.gov/known-exploited-vulnerabilities-catalog
x_refsource_MISC
https://support.apple.com/en-us/HT212256
x_refsource_MISC
https://support.apple.com/en-us/HT212257
x_refsource_MISC
https://support.apple.com/en-us/HT212258
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