CVE-2021-1879

Apple iOS, iPadOS, and watchOS — Apple iOS, iPadOS, and watchOS WebKit Cross-Site Scripting (XSS) Vulnerability
⚠️ CVSS 3.1  6.1 / 10 — MEDIUM 🔴 CISA Known Exploited Vulnerability

Overview

Apple iOS, iPadOS, and watchOS WebKit contain an unspecified vulnerability that allows for universal cross-site scripting (XSS) when processing maliciously crafted web content. This vulnerability could impact HTML parsers that use WebKit, including but not limited to Apple Safari and non-Apple products which rely on WebKit for HTML processing.

https://nvd.nist.gov/vuln/detail/CVE-2021-1879

Key Details

PropertyValue
CVE ID CVE-2021-1879
Vendor / Product Apple — iOS, iPadOS, and watchOS
NVD Published2021-04-02
NVD Last Modified2025-10-23
CVSS 3.1 Score6.1
CVSS 3.1 VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
SeverityMEDIUM
CWE CWE-79
CISA KEV Added2021-11-03
CISA KEV Deadline2021-11-17
Known Ransomware Use No

CVSS 3.1 Breakdown

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None

Required Action

CISA BOD 22-01 Deadline: 2021-11-17. Apply updates per vendor instructions.

Timeline

DateEvent
2021-11-03Added to CISA Known Exploited Vulnerabilities catalog
2021-11-17CISA BOD 22-01 remediation deadline

References

ResourceType
NVD — CVE-2021-1879 Vulnerability Database
CISA KEV Catalog Entry US Government