Is CVE-2021-30665 in the CISA KEV catalog?

Yes. CVE-2021-30665 is on the CISA Known Exploited Vulnerabilities list, added 2021-11-03.

What is the CVSS severity of CVE-2021-30665?

CVE-2021-30665 has a CVSS v3 base score of 8.8 (HIGH).

What is the EPSS score for CVE-2021-30665?

CVE-2021-30665 has an EPSS score of 3.47% (88th percentile), estimating the probability of exploitation in the next 30 days.

CVE & CISA-KEV Catalog

CVE-2021-30665

HIGHCISA KEVEPSS 88th pctl

8.8

CVSS v3

NVD

Description

A memory corruption issue was addressed with improved state management. This issue is fixed in watchOS 7.4.1, iOS 14.5.1 and iPadOS 14.5.1, tvOS 14.6, iOS 12.5.3, macOS Big Sur 11.3.1. 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..

CWE-787Out-of-bounds Write

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionRequired

ScopeUnchanged

Impact

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Exploit Intelligence

3.47%probability of exploitation in 30 days

88thpercentile

Elevated risk: more likely to be exploited than 88% of all known CVEs.

Known Exploited Vulnerability (CISA KEV)

Apple Multiple Products WebKit Memory Corruption Vulnerability

Apple iOS, iPadOS, macOS, watchOS, and tvOS WebKit contain a memory corruption 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.

Apply updates per vendor instructions.

Remediation due: 2021-11-17

References

Find and fix vulnerabilities across your fleet

TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.

Start free

This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2025-10-23.