A memory corruption issue was addressed with improved memory handling. This issue is fixed in macOS Big Sur 11.5.1, iOS 14.7.1 and iPadOS 14.7.1, watchOS 7.6.1. An application may be able to execute arbitrary code with kernel privileges. Apple is aware of a report that this issue may have been actively exploited.
CVE-2021-30807
“▲” beside the score: it is higher than NVD's CVSS score.
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 7.8 retained for reference. The 9.0 is the floor for confirmed exploitation, not an impact rating: this CVE's impact severity (EG Severity) is CVSS 7.8 HIGH under GitHub Security Advisory CVSS. Confidence: HIGH.
- Actively exploited in the wild (CISA-KEV) — the reason this is sooner than the SSVC decision on this page at low or medium mission impact
The CVE record names the fixed release — apply it.
- CVSS v3
- 7.8
- EG Score
- 9.0CRITICALhigh confidence
- EG Risk
- 75EG Risk 75/100
EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.
How it’s computed (value × EchelonGraph’s weight)Severity78% × 45%Impact severity (EG Severity): CVSS 7.8 of 10. Never the KEV-floored or EPSS-lifted EG Score.Exploitation100% × 40%Fixed at 100% for a CISA KEV listing: EchelonGraph's rule.Automatability0% × 15%CISA's SSVC Automatable value: no (Vulnrichment).SSVC (CISA's decision table, applied by EchelonGraph): Track at low, Attend at medium and Act at high mission impact.Exploitation active (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.Action: The CVE record names the fixed release. Apply it within your standard update timelines at low, sooner than that at medium and as soon as possible at high mission impact. - EPSS PROB
- 29%
- EPSS %ILE
- 98th
- KEV
- ⚠ Exploited
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (9.0): severity, escalated by confirmed exploitation. This CVE's 9.0 is the CISA KEV floor for confirmed exploitation, not an impact rating: its impact severity (EG Severity) is CVSS 7.8 HIGH.
- EG Severity
- 7.8 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
- EG Likelihood
- 29% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-22). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- CISA KEV and EG-KEV Tier 1 (exploited in the wild)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Attend at medium mission impactTrack at low, Attend at medium and Act at high mission impact.CISA BOD 26-04: 3 days & forensic triage if the affected system is publicly exposed; 14 days if it is not.Each input and its source: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at low, Attend at medium and Act at high mission impact.
The CVE record names the fixed release. Apply it within your standard update timelines at low, sooner than that at medium and as soon as possible at high mission impact.
Exploitation active (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)3 days & forensic triage if the affected system is publicly exposed; 14 days if it is not.
In CISA KEV yes (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it
CISA required action“Apply updates per vendor instructions.”
Quoted verbatim from CISA's Known Exploited Vulnerabilities catalog. CISA directs it at US federal civilian executive branch agencies under Binding Operational Directive (BOD) 26-04, which replaced BOD 22-01 on 10 June 2026; it is not EchelonGraph's advice. CISA's notes: https://nvd.nist.gov/vuln/detail/CVE-2021-30807
Published
October 19, 2021
Last Modified
October 23, 2025
Advisory Details (4)
Auto-updated Oct 19, 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-2021-30807About the security content of watchOS 7.6.1 - Apple Support
https://support.apple.com/en-us/HT212713About the security content of iOS 14.7.1 and iPadOS 14.7.1 - Apple Support
https://support.apple.com/en-us/HT212623About the security content of macOS Big Sur 11.5.1 - Apple Support
https://support.apple.com/en-us/HT212622Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 22× in last 7d / 190× in last 30d)
Each row is a time one of our pipelines fetched, updated or re-scored this CVE. 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. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.
Showing the most recent 100 of 1,112 refreshes on record for this CVE.
A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 1,012 oldest rows on record are not shown and were not checked, so the counts can still include repeats.
- 2026-10-23 16:28 UTCEPSS rescoreEPSS 29% · 98th percentile
- 2026-10-23 14:34 UTCEG score recompute
- 2026-10-23 14:34 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-22 16:29 UTCEPSS rescoreEPSS 29% · 98th percentile
- 2026-10-22 15:57 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-21 17:23 UTCEG score recompute
- 2026-10-21 17:23 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-21 16:28 UTCEPSS rescoreEPSS 29% · 98th percentile
- 2026-10-20 18:47 UTCEG score recompute
- 2026-10-20 18:47 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-20 16:28 UTCEPSS rescoreEPSS 29% · 98th percentile
- 2026-10-19 20:14 UTCEG score recompute
- 2026-10-19 20:13 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-19 16:28 UTCEPSS rescoreEPSS 29% · 98th percentile
- 2026-10-18 21:39 UTCEG score recompute
- 2026-10-18 21:38 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-18 09:03 UTCEG score recompute
- 2026-10-17 23:04 UTCEG score recompute
- 2026-10-17 23:04 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-17 16:28 UTCEPSS rescoreEPSS 29% · 98th percentile
- 2026-10-17 00:29 UTCEG score recompute
- 2026-10-17 00:29 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-16 16:33 UTCEPSS rescoreEPSS 29% · 98th percentile
- 2026-10-16 01:54 UTCEG score recompute
- 2026-10-16 01:54 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
Show 75 moreShow fewer
- 2026-10-15 16:28 UTCEPSS rescoreEPSS 29% · 98th percentile
- 2026-10-15 03:19 UTCEG score recompute
- 2026-10-15 03:19 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-14 16:28 UTCEPSS rescoreEPSS 29% · 98th percentile
- 2026-10-14 04:43 UTCEG score recompute
- 2026-10-14 04:43 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-13 16:28 UTCEPSS rescoreEPSS 29% · 98th percentile
- 2026-10-13 06:06 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-12 19:17 UTCEG score recompute
- 2026-10-12 16:29 UTCEPSS rescoreEPSS 29% · 98th percentile
- 2026-10-12 07:32 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-12 03:27 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-11 23:23 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-11 19:22 UTCEG score recompute
- 2026-10-11 19:21 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-11 15:20 UTCEG score recompute
- 2026-10-11 15:20 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-11 13:43 UTCEPSS rescoreEPSS 29% · 98th percentile
- 2026-10-11 11:18 UTCEG score recompute
- 2026-10-11 11:18 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-11 07:14 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-11 03:13 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-10 23:10 UTCEG score recompute
- 2026-10-10 23:10 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-10 19:56 UTCEPSS rescoreEPSS 29% · 98th percentile
- 2026-10-10 19:08 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-10 15:06 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-10 11:04 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-10 07:02 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-10 03:02 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-09 23:01 UTCEG score recompute
- 2026-10-09 23:01 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-09 20:04 UTCEPSS rescoreEPSS 29% · 98th percentile
- 2026-10-09 18:59 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-09 14:58 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-09 10:55 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-09 06:53 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-09 02:51 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-08 22:50 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-08 18:48 UTCEG score recompute
- 2026-10-08 18:48 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-08 16:39 UTCEPSS rescoreEPSS 29% · 98th percentile
- 2026-10-08 14:47 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-08 10:45 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-08 06:44 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-08 02:43 UTCEG score recompute
- 2026-10-08 02:43 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-07 23:44 UTCEPSS rescoreEPSS 29% · 98th percentile
- 2026-10-07 22:40 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-07 18:39 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-07 14:38 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-07 10:36 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-07 06:33 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-07 02:31 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-06 22:29 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-06 18:28 UTCEG score recompute
- 2026-10-06 18:28 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-06 15:14 UTCEPSS rescoreEPSS 29% · 98th percentile
- 2026-10-06 14:26 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-06 10:25 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-06 06:24 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-06 02:23 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-05 22:21 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-05 18:19 UTCEG score recompute
- 2026-10-05 18:19 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-05 17:40 UTCEPSS rescoreEPSS 29% · 98th percentile
- 2026-10-05 14:18 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-05 10:17 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-05 06:17 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-05 02:16 UTCEG score recompute
- 2026-10-05 02:16 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-04 23:19 UTCEPSS rescoreEPSS 29% · 98th percentile
- 2026-10-04 22:15 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-04 18:14 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
- 2026-10-04 14:12 UTCGHSA enrichmentGHSA-676h-wcx2-4w5q · GitHub severity HIGH · GitHub CVSS 7.8
Publicly available exploits
(2 references)Public exploit code is referenced for this CVE (2 GitHub PoCs). Defenders should treat patch urgency accordingly.
- GitHub PoC30440r/gexPublished Nov 30, 2021
Gex is an iOS 14.7 jailbreak using CVE-2021-30807 IOMFB & CVE-2021-30860 exploit(s)
Open source ↗ - GitHub PoCjsherman212/iomfb-exploitPublished Oct 9, 2021
Exploit for CVE-2021-30807
Open source ↗
Related CVEs(same CWE)
Frequently asked(6)
What is CVE-2021-30807?
When was the CVE record for CVE-2021-30807 published?
Is CVE-2021-30807 actively exploited?
What is the CVSS score of CVE-2021-30807?
Which products are affected by CVE-2021-30807?
How do I remediate CVE-2021-30807?
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2021-30807
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