Privilege escalation via incorrect WebRender boundary conditions
Published Sep 15, 2026 · Updated Sep 15, 2026
Incorrect boundary conditions in Mozilla Firefox before 156 allow attackers to gain elevated privileges through Graphics: WebRender. Mozilla has not published the WebRender operation, attacker-controlled input, or failed boundary check that produces the escalation. Firefox ESR branches before 115.41, 140.16, and 153.3 are also affected; the access level, delivery path, user interaction, and resulting privileges remain undisclosed.
Summary
What happened
Incorrect boundary conditions in Mozilla Firefox before 156 allow attackers to gain elevated privileges through Graphics: WebRender. Mozilla has not published the WebRender operation, attacker-controlled input, or failed boundary check that produces the escalation. Firefox ESR branches before 115.41, 140.16, and 153.3 are also affected; the access level, delivery path, user interaction, and resulting privileges remain undisclosed.
The record
- CVE
- CVE-2026-92020
- Published
- Sep 15, 2026
- Updated
- Sep 15, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- Unavailable
- Attack vector
- Unavailable
- Privileges
- Unavailable
Timeline
How it unfolded
- Sep 15, 2026CVE publishedPublication date reported by the CVE source.
- Sep 15, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
Published CVSS scores
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CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
No sourced classifications are available.
Public exploit references
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Technologies
Your stack
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Your stack
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