CVE-2021-30666: Apple iOS WebKit Buffer Overflow Vulnerability
Actively exploited. At least one CVE in this advisory is listed in the CISA Known Exploited Vulnerabilities catalog — exploitation has been observed in the wild. Treat remediation as urgent.
Apple iOS WebKit contains a buffer-overflow vulnerability that leads to code execution 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.
CSIRTS triage
- What
- There is a buffer-overflow vulnerability that leads to code execution when processing maliciously crafted web content.
- Who is affected
- Deployments of Apple iOS WebKit, including Apple Safari and other products relying on WebKit.
- Urgency
- Remediation is urgent due to active exploitation and critical severity.
- Action
- Update to the latest version of iOS WebKit.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2021-30666
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Exploitation confirmedCVE-2021-30666Already exploited in the wild (CISA KEV) — the prediction phase is over. Patch now. Riskier than 86% of all EPSS-scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2021-30666 | coverage & exploitation status | NVD · CVE.org |
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