Is CVE-2021-30657 being actively exploited?

Yes. CVE-2021-30657 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added on November 3, 2021.

What is the CVSS score for CVE-2021-30657?

CVE-2021-30657 has a CVSS 3.1 base score of 5.5 (MEDIUM).

CVE-2021-30657

MEDIUM · CVSS 5.5CISA KEV: actively exploitedEPSS 68.5%EU EUVD: exploited

A logic issue was addressed with improved state management. This issue is fixed in macOS Big Sur 11.3, Security Update 2021-002 Catalina. A malicious application may bypass Gatekeeper checks. Apple is aware of a report that this issue may have been actively exploited..

Key facts

CVSS score: 5.5 (v3.1)
Severity: MEDIUM
CVSS vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
Weakness (CWE): CWE-862
EPSS score: 68.5% (99th percentile)
In CISA KEV: Yes, added November 3, 2021
In EU EUVD: Yes (EUVD-2021-17574)
Published: September 8, 2021
NVD last modified: June 17, 2026
Status: Analyzed

CISA Known Exploited Vulnerability

Apple macOS Unspecified Vulnerability

Added to the KEV catalog on November 3, 2021; federal remediation due November 17, 2021.

EU Vulnerability Database (EUVD)

This vulnerability is also tracked by ENISA as EUVD-2021-17574 in the EU Vulnerability Database. ENISA flags it as known exploited. Last updated in EUVD on October 21, 2025.

View on the EU Vulnerability Database

Affected products

apple / mac os x
apple / mac os x
apple / mac os x
apple / mac os x
apple / mac os x
apple / mac os x
apple / mac os x
apple / mac os x
apple / mac os x
apple / macos

Certified products that may be affected

1 FIPS 140 or Common Criteria certified product, from automated matching by sec-certs.org.

Apple macOS 11 Big Sur: Contacts - Apple Inc. - Common Criteria CCEVS-VR-VID-11243-2022 - archived

References

https://support.apple.com/en-us/HT212325(Release Notes, Vendor Advisory)
https://support.apple.com/en-us/HT212326(Release Notes, Vendor Advisory)
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-30657(Third Party Advisory, US Government Resource)

Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS

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