CVEs / CVE-2021-1879
CVE-2021-1879: Apple iOS, iPadOS, and watchOS WebKit Cross-Site Scripting (XSS) Vulnerability
- Known exploited in the CISA KEV catalog since 3 Nov 2021
- medium 6.1 CVSS 3.1 (NVD)
- EPSS 7.08% chance of exploitation in the next 30 days, higher than 94% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
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.
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..
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| Apple iOS and iPadOS | from unspecified, before 14.4 | 14.4 |
| Apple iOS | from unspecified, before 12.5 | 12.5 |
| Apple watchOS | from unspecified, before 7.3 | 7.3 |
Exploitation
| In CISA KEV since | 3 Nov 2021 |
|---|---|
| Due date for US federal agencies | 17 Nov 2021 |
| Used in ransomware campaigns | Unknown |
| Required action | Apply updates per vendor instructions. |
Severity
| CVSS 3.1 | 6.1 mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:NScored by NVD |
|---|---|
| Weakness | CWE-79 |
References
- CVE-2021-1879 on NVD
- CVE-2021-1879 in the CISA KEV catalog
- https://support.apple.com/en-us/HT212256 Release Notes, Vendor Advisory
- https://support.apple.com/en-us/HT212257 Release Notes, Vendor Advisory
- https://support.apple.com/en-us/HT212258 Release Notes, Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-1879 US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.