Sandbox escape via CoreMedia out-of-bounds write
Published Sep 14, 2026 · Updated Sep 14, 2026
An out-of-bounds write in CoreMedia across affected Apple operating systems allows sandboxed processes to bypass sandbox restrictions. CoreMedia performs a write beyond its intended buffer because its bounds check does not adequately constrain the operation; Apple has not disclosed the affected function or input format. Exploitation requires code already executing inside a sandbox and is bounded to bypassing that sandbox, with no further impact published.
Summary
What happened
An out-of-bounds write in CoreMedia across affected Apple operating systems allows sandboxed processes to bypass sandbox restrictions. CoreMedia performs a write beyond its intended buffer because its bounds check does not adequately constrain the operation; Apple has not disclosed the affected function or input format. Exploitation requires code already executing inside a sandbox and is bounded to bypassing that sandbox, with no further impact published.
The record
- CVE
- CVE-2026-86876
- Published
- Sep 14, 2026
- Updated
- Sep 14, 2026
- Vendor
- Apple
- Product
- iOS and iPadOS
- Classifications
- T1068
- Attack vector
- local
- Privileges
- Unavailable
Timeline
How it unfolded
- Sep 14, 2026CVE publishedPublication date reported by the CVE source.
- Sep 14, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=0 <26.7
- Affected versionversion=0 <27
What conditions does exploitation require?
What is affected?
Published CVSS scores
No CVSS assessment is available in this record.
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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