Sandbox escape via permissive process token DACL
Published May 26, 2020 · Updated Aug 4, 2024
Sandbox escape in Mozilla Firefox before 76 and Firefox ESR before 68.8 allows attackers to escape a content-process sandbox on Windows. The Level 5 sandbox's primary-token default DACL grants one content process full access to peers, enabling capture of a newly spawned process before its privileged impersonation token is dropped. Exploitation requires code already running in one content process; successful abuse escapes the browser sandbox but does not itself establish initial code execution.
Summary
What happened
Sandbox escape in Mozilla Firefox before 76 and Firefox ESR before 68.8 allows attackers to escape a content-process sandbox on Windows. The Level 5 sandbox's primary-token default DACL grants one content process full access to peers, enabling capture of a newly spawned process before its privileged impersonation token is dropped. Exploitation requires code already running in one content process; successful abuse escapes the browser sandbox but does not itself establish initial code execution.
The record
- CVE
- CVE-2020-12388
- Published
- May 26, 2020
- Updated
- Aug 4, 2024
- Vendor
- Mozilla
- Product
- Firefox
- Classifications
- CWE-20, T1068
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 26, 2020CVE publishedPublication date reported by the CVE source.
- Aug 4, 2024Record 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=unspecified <76
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- Project Zero Firefox sandbox-escape proof of conceptfunctional · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
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Your stack
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