Sandbox escape via unvalidated privileged CSS rule insertion
Published Jun 19, 2023 · Updated Dec 11, 2024
Code injection in Firefox before 70 allows attackers to escape the sandbox and execute privileged code via a compromised content process. SelectParentHelper accepted CSS values from child-to-parent IPC and inserted them into privileged rules without restricting selectors or parsing values safely. Exploitation requires prior code execution in a content process; the demonstrated escape used XBL bindings to resolve Windows APIs and invoke WinExec.
Summary
What happened
Code injection in Firefox before 70 allows attackers to escape the sandbox and execute privileged code via a compromised content process. SelectParentHelper accepted CSS values from child-to-parent IPC and inserted them into privileged rules without restricting selectors or parsing values safely. Exploitation requires prior code execution in a content process; the demonstrated escape used XBL bindings to resolve Windows APIs and invoke WinExec.
The record
- CVE
- CVE-2019-25136
- Published
- Jun 19, 2023
- Updated
- Dec 11, 2024
- Vendor
- Mozilla
- Product
- Firefox
- Classifications
- T1068
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 19, 2023CVE publishedPublication date reported by the CVE source.
- Dec 11, 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 <70
What conditions does exploitation require?
What is affected?
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
No public exploit references are available in this record.
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Reported exploitation
- Heliconia Files sandbox-escape exploitationreported exploitation
Technologies
Your stack
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Your stack
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