# CVE-2021-1879: Apple iOS, iPadOS, and watchOS WebKit Cross-Site Scripting (XSS) Vulnerability

- Exploited (CISA KEV): yes, added 2021-11-03
- Published: 2021-04-02
- CVSS: 6.1 MEDIUM (v3.1)
- EPSS: 7.1% (94th percentile)
- CWE: CWE-79

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..

## Edge WAF coverage (claimed by vendors, not measured)

| Vendor | Status | First rule | Days after publication |
|---|---|---|---|
| Cloudflare | Before feed history | — | — |
| AWS | No public claim | — | — |
| Microsoft Azure | No public claim | — | — |
| Google Cloud | Before feed history | — | — |
| Fastly | Before feed history | — | — |
| F5 | Before feed history | — | — |
| Akamai | No public source | — | — |
| OWASP CRS | Before feed history | — | — |

"No public claim" means no vendor statement names this CVE; "Before feed history" means the CVE is older than the vendor feed. In both cases generic rules may still block it.

HTML: https://cve.vigilbase.com/cve/CVE-2021-1879 · JSON: https://cve.vigilbase.com/api/v1/cves/CVE-2021-1879