CVE-2021-1871

criticalknown exploitedcovered by 1 sourcefirst seen 2021-11-03

Actively exploited. CVE-2021-1871 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, and macOS WebKit contain an unspecified logic vulnerability that allows a remote attacker to execute code. 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: An unspecified logic vulnerability in WebKit allows remote code execution by attackers.
Who is affected: Users of Apple iOS, iPadOS, and macOS with WebKit are affected.
Urgency: Remediation is urgent as exploitation is possible and the vulnerability is critical.
Action: Update to the latest versions of iOS, iPadOS, and macOS to mitigate the vulnerability.

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 93% of all EPSS-scored CVEs.

Advisory coverage (1)

criticalexploitedCVE-2021-1871: Apple iOS, iPadOS, and macOS WebKit Remote Code Execution Vulnerabilitycisa-kev · 2021-11-03

External references

NVD record for CVE-2021-1871

CVE.org record

CISA KEV catalog

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