No exploitation reportedFix available

CVE-2021-30743

Q: Is CVE-2021-30743 actively exploited?

Active exploitation of CVE-2021-30743 has not been confirmed. Its EPSS score was 1.2% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

Q: What is the CVSS score for CVE-2021-30743?

CVE-2021-30743 has a CVSS v3 base score of 7.8 (HIGH severity), with vector string CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

No exploitation reported by the sources we read.

Published2021-09-08
WeaknessCWE-787

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

An out-of-bounds write was addressed with improved input validation. This issue is fixed in iOS 14.5 and iPadOS 14.5, watchOS 7.4, Security Update 2021-003 Catalina, tvOS 14.5, macOS Big Sur 11.3. Processing a maliciously crafted image may lead to arbitrary code execution.

Timeline

dates in UTC

2021-09-0814:15CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-30743?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-30743?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD

Apple mac os x

Branch	Affected	Fixed in	Source
10.15	= 10.15	no fix published	NVD
10.15	= 10.15.1	no fix published	NVD
10.15	= 10.15.2	no fix published	NVD
10.15	= 10.15.3	no fix published	NVD
10.15	= 10.15.4	no fix published	NVD
10.15	= 10.15.5	no fix published	NVD
10.15	= 10.15.6	no fix published	NVD
10.15	= 10.15.7	no fix published	NVD

Apple ipados

Branch	Affected	Fixed in	Source
14.5	< 14.5	14.5	NVD

Apple iphone os

Branch	Affected	Fixed in	Source
14.5	< 14.5	14.5	NVD

3 more products in the sources.

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

Advisories and patches

support.apple.comVendor Advisory
support.apple.comVendor Advisory
support.apple.comVendor Advisory
support.apple.comVendor Advisory
support.apple.comVendor Advisory

Detection

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: none listed

Sources

NVDCVSS 3.17.8read 2026-10-23
NVDCVSS 2.06.8read 2026-10-23
NVDweakness (CWE)CWE-787read 2026-10-23
FIRST EPSSEPSS score1.2 %2026-10-23

Technical details

CVSS v3 Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Published: 2021-09-08
Last Modified: 2026-06-17
NVD status: Modified

Frequently asked questions

What is CVE-2021-30743?

Is CVE-2021-30743 actively exploited?

Active exploitation of CVE-2021-30743 has not been confirmed. Its EPSS score was 1.2% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-30743?

CVE-2021-30743 has a CVSS v3 base score of 7.8 (HIGH severity), with vector string CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

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