Browser spoofing via suppressed fullscreen exit shortcuts
Published Jul 5, 2023 · Updated Feb 13, 2025
Fullscreen exit prevention in Mozilla Firefox before 115 allows remote attackers to spoof browser chrome through a malicious website. A suppressed key event becomes default-prevented in the content process, and GlobalKeyListener then skips the F11 handler instead of reserving the exit shortcut. A victim must visit the attacker-controlled page and enter browser fullscreen; an alert or prompt can then keep the page fullscreen and support interface spoofing.
Summary
What happened
Fullscreen exit prevention in Mozilla Firefox before 115 allows remote attackers to spoof browser chrome through a malicious website. A suppressed key event becomes default-prevented in the content process, and GlobalKeyListener then skips the F11 handler instead of reserving the exit shortcut. A victim must visit the attacker-controlled page and enter browser fullscreen; an alert or prompt can then keep the page fullscreen and support interface spoofing.
The record
- CVE
- CVE-2023-37210
- Published
- Jul 5, 2023
- Updated
- Feb 13, 2025
- Vendor
- Mozilla
- Product
- Firefox
- Classifications
- CWE-346, T1036
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 5, 2023CVE publishedPublication date reported by the CVE source.
- Feb 13, 2025Record 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 <115
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
- pocfullscreen.htmlproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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