CVE-2021-30663

criticalknown exploitedcovered by 1 sourcefirst seen 2021-11-03

Actively exploited. CVE-2021-30663 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03) — exploitation has been observed in the wild, and US federal agencies are required to remediate it under BOD 22-01. Treat patching as urgent.

Apple iOS, iPadOS, macOS, tvOS, and Safari WebKit contain an integer 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

vendor: Apple Remote code execution

What: An integer overflow vulnerability leads to code execution when processing malicious web content.
Who is affected: Users of Apple iOS, iPadOS, macOS, tvOS, and Safari WebKit.
Urgency: Immediate remediation is necessary due to active exploitation and critical severity.
Action: Update to the latest version of affected Apple products.

AI-assisted analysis generated from the source advisory — verify against the original.

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Exploitation outlook

Exploitation confirmedAlready exploited in the wild (CISA KEV) — the prediction phase is over. Patch now. Riskier than 88% of all EPSS-scored CVEs.

Advisory coverage (1)

criticalexploitedCVE-2021-30663: Apple Multiple Products WebKit Integer Overflow Vulnerabilitycisa-kev · 2021-11-03

External references

NVD record for CVE-2021-30663

CVE.org record

CISA KEV catalog

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