CVE-2021-30939 json
An out-of-bounds read was addressed with improved bounds checking.
published 2021-08-24 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-17856
- cvss
- 7.8
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 4.0%
- EPSS 4.0% chance of exploitation in 30 days, percentile 90%
- public exploits
- 0
- none known
Summary
An out-of-bounds read was addressed with improved bounds checking. This issue is fixed in macOS Big Sur 11.6.2, tvOS 15.2, macOS Monterey 12.1, Security Update 2021-008 Catalina, iOS 15.2 and iPadOS 15.2, watchOS 8.3. Processing a maliciously crafted image may lead to arbitrary code execution.
Patch / fix
- Apple watchOS 8.3
- Apple iOS and iPadOS 15.2
- Apple macOS 11.6, 12.1, 15.2, 2021
Exploit prediction
4.05% chance of exploitation in the next 30 days, higher than 90% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 7.8 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 6.8 | AV:N/AC:M/Au:N/C:P/I:P/A:P |
Affected products
- Apple watchOS
- Apple iOS and iPadOS
- Apple macOS
Classification
- Weakness
-
- CWE-125 Out-of-bounds Read
References
- support.apple.com /en-us/HT212975
- support.apple.com /en-us/HT212976
- support.apple.com /en-us/HT212978
- support.apple.com /en-us/HT212979
- support.apple.com /en-us/HT212981
- support.apple.com /en-us/HT212980
- talosintelligence.com /vulnerability_reports/TALOS-2021-1414
- zerodayinitiative.com /advisories/ZDI-22-359/
Sources
- CVE List CVE-2021-30939
- NVD CVE-2021-30939
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