Sandbox escape via callback lifetime mismanagement
Published Sep 11, 2023 · Updated Dec 18, 2025
Use-after-free in Mozilla Firefox, Firefox ESR, and Thunderbird allows remote attackers to escape the content-process sandbox. Concurrent FilePickerShownCallback instances keep raw pointers to one FilePickerParent, and one Done() call destroys the shared object before later callbacks use it. Exploitation requires prior code execution in a compromised content process and user interaction to close multiple file-picker dialogs; the documented result is a parent-process crash that escapes the sandbox.
Summary
What happened
Use-after-free in Mozilla Firefox, Firefox ESR, and Thunderbird allows remote attackers to escape the content-process sandbox. Concurrent FilePickerShownCallback instances keep raw pointers to one FilePickerParent, and one Done() call destroys the shared object before later callbacks use it. Exploitation requires prior code execution in a compromised content process and user interaction to close multiple file-picker dialogs; the documented result is a parent-process crash that escapes the sandbox.
The record
- CVE
- CVE-2023-4575
- Published
- Sep 11, 2023
- Updated
- Dec 18, 2025
- Vendor
- Mozilla
- Product
- Firefox
- Classifications
- CWE-416, T1068
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 11, 2023CVE publishedPublication date reported by the CVE source.
- Dec 18, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=unspecified <117
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.
Public exploit references
- Mozilla Bugzilla crash reproducerproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo