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..
CVE-2021-30657
Score elevated to 9.0 because this CVE is listed on the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03), indicating real-world exploitation has been confirmed by US federal agencies. NVD baseline CVSS 5.5 retained for reference. Confidence: HIGH.
- Actively exploited in the wild (CISA-KEV)
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 5.5
- EG Score
- 9.0(high)
- EPSS
- 99.3%
- KEV
- ⚠ Exploited
Published
September 8, 2021
Last Modified
October 23, 2025
Advisory Details (3)
Auto-updated Jun 13, 2026Known Exploited Vulnerabilities Catalog | CISA
Known Exploited Vulnerabilities Catalog | CISA. Listed in CISA Known Exploited Vulnerabilities catalog.
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-30657About the security content of Security Update 2021-002 Catalina - Apple Support
https://support.apple.com/en-us/HT212326About the security content of macOS Big Sur 11.3 - Apple Support
https://support.apple.com/en-us/HT212325Weakness Classification(2)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 58× in last 7d / 224× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
Showing the most recent 100 of 393 total refreshes for this CVE.
- 2026-07-22 20:08 UTCGHSA enrichment
- 2026-07-22 19:40 UTCCISA KEV update
- 2026-07-22 16:07 UTCEG score recompute
- 2026-07-22 16:07 UTCGHSA enrichment
- 2026-07-22 14:06 UTCEPSS rescore
- 2026-07-22 14:06 UTCEPSS rescore
- 2026-07-22 11:59 UTCGHSA enrichment
- 2026-07-22 07:59 UTCGHSA enrichment
- 2026-07-22 03:59 UTCGHSA enrichment
- 2026-07-21 23:59 UTCGHSA enrichment
- 2026-07-21 19:56 UTCGHSA enrichment
- 2026-07-21 15:54 UTCEG score recompute
- 2026-07-21 15:53 UTCGHSA enrichment
- 2026-07-21 15:22 UTCEPSS rescore
- 2026-07-21 15:22 UTCEPSS rescore
- 2026-07-21 14:37 UTCCISA KEV update
- 2026-07-21 11:52 UTCGHSA enrichment
- 2026-07-21 07:52 UTCGHSA enrichment
- 2026-07-21 03:50 UTCGHSA enrichment
- 2026-07-20 23:49 UTCGHSA enrichment
- 2026-07-20 19:48 UTCEG score recompute
- 2026-07-20 19:48 UTCGHSA enrichment
- 2026-07-20 17:05 UTCEPSS rescore
- 2026-07-20 15:48 UTCGHSA enrichment
- 2026-07-20 11:48 UTCGHSA enrichment
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- 2026-07-20 07:48 UTCGHSA enrichment
- 2026-07-20 03:48 UTCGHSA enrichment
- 2026-07-19 23:48 UTCGHSA enrichment
- 2026-07-19 19:47 UTCGHSA enrichment
- 2026-07-19 15:47 UTCGHSA enrichment
- 2026-07-19 11:45 UTCGHSA enrichment
- 2026-07-19 07:44 UTCGHSA enrichment
- 2026-07-19 03:44 UTCEG score recompute
- 2026-07-19 03:44 UTCGHSA enrichment
- 2026-07-19 02:27 UTCEPSS rescore
- 2026-07-19 02:27 UTCEPSS rescore
- 2026-07-18 23:44 UTCGHSA enrichment
- 2026-07-18 19:44 UTCGHSA enrichment
- 2026-07-18 15:44 UTCGHSA enrichment
- 2026-07-18 11:43 UTCGHSA enrichment
- 2026-07-18 07:43 UTCGHSA enrichment
- 2026-07-18 03:42 UTCGHSA enrichment
- 2026-07-17 23:42 UTCGHSA enrichment
- 2026-07-17 19:41 UTCGHSA enrichment
- 2026-07-17 15:41 UTCGHSA enrichment
- 2026-07-17 11:41 UTCGHSA enrichment
- 2026-07-17 07:41 UTCEG score recompute
- 2026-07-17 07:41 UTCGHSA enrichment
- 2026-07-17 03:41 UTCGHSA enrichment
- 2026-07-16 23:41 UTCGHSA enrichment
- 2026-07-16 19:41 UTCGHSA enrichment
- 2026-07-16 17:04 UTCCISA KEV update
- 2026-07-16 17:00 UTCEPSS rescore
- 2026-07-16 15:41 UTCGHSA enrichment
- 2026-07-16 11:40 UTCGHSA enrichment
- 2026-07-16 07:40 UTCGHSA enrichment
- 2026-07-16 03:40 UTCGHSA enrichment
- 2026-07-15 23:40 UTCGHSA enrichment
- 2026-07-15 19:40 UTCGHSA enrichment
- 2026-07-15 16:55 UTCEPSS rescore
- 2026-07-15 16:55 UTCEPSS rescore
- 2026-07-15 16:49 UTCCISA KEV update
- 2026-07-15 15:39 UTCGHSA enrichment
- 2026-07-15 15:04 UTCCISA KEV update
- 2026-07-15 11:38 UTCGHSA enrichment
- 2026-07-15 07:37 UTCGHSA enrichment
- 2026-07-15 03:36 UTCGHSA enrichment
- 2026-07-14 23:36 UTCGHSA enrichment
- 2026-07-14 19:35 UTCGHSA enrichment
- 2026-07-14 18:05 UTCCISA KEV update
- 2026-07-14 15:34 UTCGHSA enrichment
- 2026-07-14 11:34 UTCGHSA enrichment
- 2026-07-14 07:34 UTCGHSA enrichment
- 2026-07-14 03:34 UTCGHSA enrichment
- 2026-07-13 23:33 UTCGHSA enrichment
- 2026-07-13 19:32 UTCGHSA enrichment
- 2026-07-13 17:07 UTCCISA KEV update
- 2026-07-13 15:31 UTCGHSA enrichment
- 2026-07-13 11:31 UTCGHSA enrichment
- 2026-07-13 07:31 UTCGHSA enrichment
- 2026-07-13 06:10 UTCEPSS rescore
- 2026-07-13 03:31 UTCGHSA enrichment
- 2026-07-12 23:31 UTCGHSA enrichment
- 2026-07-12 19:31 UTCGHSA enrichment
- 2026-07-12 15:30 UTCGHSA enrichment
- 2026-07-12 11:29 UTCGHSA enrichment
- 2026-07-12 07:29 UTCGHSA enrichment
- 2026-07-12 05:44 UTCEPSS rescore
- 2026-07-12 05:44 UTCEPSS rescore
- 2026-07-12 03:29 UTCGHSA enrichment
- 2026-07-11 23:29 UTCGHSA enrichment
- 2026-07-11 19:29 UTCGHSA enrichment
- 2026-07-11 15:28 UTCGHSA enrichment
- 2026-07-11 11:28 UTCGHSA enrichment
- 2026-07-11 07:28 UTCGHSA enrichment
- 2026-07-11 03:28 UTCGHSA enrichment
- 2026-07-10 23:27 UTCGHSA enrichment
- 2026-07-10 19:26 UTCGHSA enrichment
- 2026-07-10 17:52 UTCCISA KEV update
- 2026-07-10 15:26 UTCGHSA enrichment
Publicly available exploits
(2 references)Working exploit code is in the public domain (1 Metasploit module) (1 GitHub PoC). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.
- GitHub PoCshubham0d/CVE-2021-30657First seen Nov 7, 2021
A sample POC for CVE-2021-30657 affecting MacOS
Open source ↗ - Metasploitexploit/osx/browser/osx_gatekeeper_bypass✓ verifiedFirst seen Mar 25, 2021
macOS Gatekeeper check bypass
Open source ↗
Related CVEs(same CWE)
Same CWE
10 shownCWE-862 · CWE-494
Frequently asked(6)
What is CVE-2021-30657?
When was CVE-2021-30657 disclosed?
Is CVE-2021-30657 actively exploited?
What is the CVSS score of CVE-2021-30657?
Which products are affected by CVE-2021-30657?
How do I remediate CVE-2021-30657?
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2021-30657
Is Your Infrastructure Affected by CVE-2021-30657?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.