Sandbox escape via brokered pseudo-handle conversion
Published Mar 26, 2025 · Updated Feb 26, 2026
Incorrect handle handling in Google Chrome before 134.0.6998.177 on Windows allows remote attackers to escape its sandbox via a malicious file. Mojo's ipcz broker passes a renderer-supplied -2 thread pseudo-handle to DuplicateHandle, which converts it into a real browser-process thread handle and returns it to the renderer. A victim must open attacker-controlled content; the leaked handle enables browser-process code execution outside the renderer sandbox.
Summary
What happened
Incorrect handle handling in Google Chrome before 134.0.6998.177 on Windows allows remote attackers to escape its sandbox via a malicious file. Mojo's ipcz broker passes a renderer-supplied -2 thread pseudo-handle to DuplicateHandle, which converts it into a real browser-process thread handle and returns it to the renderer. A victim must open attacker-controlled content; the leaked handle enables browser-process code execution outside the renderer sandbox.
The record
- CVE
- CVE-2025-2783
- Published
- Mar 26, 2025
- Updated
- Feb 26, 2026
- Vendor
- Google Cloud
- Product
- Google Chrome
- Classifications
- T1203
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Mar 1, 2025Exploitation reportedOperation ForumTroll
- Mar 26, 2025CVE publishedPublication date reported by the CVE source.
- Mar 27, 2025Exploitation reportedCISA Known Exploited Vulnerabilities entry
- Feb 26, 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=134.0.6998.177 <134.0.6998.177
What conditions does exploitation require?
What is affected?
Published CVSS scores
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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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Reported exploitation
- Operation ForumTrollthreat actor
- Google reports exploitation in the wildreported exploitation
- CISA Known Exploited Vulnerabilities entryknown exploited catalog
Technologies
Your stack
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Your stack
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