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Actively exploited · Published Sep 8, 2021 · Assigned by apple

CVE-2021-30666

High 8.8 Exploited

In plain English

A high-severity memory corruption in iOS from Apple. Attackers are actively exploiting it in the wild (listed by CISA on November 3, 2021). The chance it is exploited in the next 30 days is estimated at 3.0% (higher than 87% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)8.8High
Exploit odds (30 days)3.0%top 12.6% of all CVEs
Exploited in the wildYesCISA KEV since Nov 3, 2021
Attack toolingNoneno public tooling known

CISA guidance

Apply updates per vendor instructions.

Federal agencies must remediate by Nov 17, 2021.

Official description

A buffer overflow issue was addressed with improved memory handling. This issue is fixed in iOS 12.5.3. Processing maliciously crafted web content may lead to arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited..

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Alpine:v3.20webkit2gtk2.26.0-r0ALPINE-CVE-2021-30666
Debian:12webkit2gtk2.26.1-2DEBIAN-CVE-2021-30666
Debian:13webkit2gtk2.26.1-2DEBIAN-CVE-2021-30666
Debian:14webkit2gtk2.26.1-2DEBIAN-CVE-2021-30666
Debian:12wpewebkit2.26.3-1DEBIAN-CVE-2021-30666
Debian:13wpewebkit2.26.3-1DEBIAN-CVE-2021-30666
Debian:14wpewebkit2.26.3-1DEBIAN-CVE-2021-30666
Ubuntu:22.04:LTSqtwebkit-opensource-srcno fix listedUBUNTU-CVE-2021-30666
Ubuntu:24.04:LTSqtwebkit-opensource-srcno fix listedUBUNTU-CVE-2021-30666
Ubuntu:22.04:LTSwpewebkitno fix listedUBUNTU-CVE-2021-30666

Affected products (as reported)

VendorProductVersions
Apple iOS unspecified – before 12.5

Weakness: CWE-119 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

References