Site isolation bypass via FileAPI race
Published Sep 9, 2026 · Updated Sep 10, 2026
Race condition in Google Chrome FileAPI before 153.0.8010.36 allows remote attackers to bypass site isolation via crafted HTML. Google has not disclosed the specific FileAPI locus or the competing operations whose ordering breaks the isolation boundary. Exploitation requires prior renderer-process compromise; the published impact is limited to bypassing site isolation, with no more specific consequence stated.
Summary
What happened
Race condition in Google Chrome FileAPI before 153.0.8010.36 allows remote attackers to bypass site isolation via crafted HTML. Google has not disclosed the specific FileAPI locus or the competing operations whose ordering breaks the isolation boundary. Exploitation requires prior renderer-process compromise; the published impact is limited to bypassing site isolation, with no more specific consequence stated.
The record
- CVE
- CVE-2026-87433
- Published
- Sep 9, 2026
- Updated
- Sep 10, 2026
- Vendor
- Google Cloud
- Product
- Google Chrome
- Classifications
- CWE-367, T1203
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 9, 2026CVE publishedPublication date reported by the CVE source.
- Sep 10, 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?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=153.0.8010.36 <153.0.8010.36
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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