Privilege escalation from web content
Published Jul 21, 2026 · Updated Jul 21, 2026
Privilege escalation in Mozilla Firefox and Thunderbird before 153 allows remote attackers to gain elevated application privileges via web content. The flaw resides in DOM Workers, but Mozilla has not disclosed the affected function, incorrect operation, or crossed privilege boundary. Exploitation requires user interaction, and the elevated actions available to the attacker remain undisclosed.
Summary
What happened
Privilege escalation in Mozilla Firefox and Thunderbird before 153 allows remote attackers to gain elevated application privileges via web content. The flaw resides in DOM Workers, but Mozilla has not disclosed the affected function, incorrect operation, or crossed privilege boundary. Exploitation requires user interaction, and the elevated actions available to the attacker remain undisclosed.
The record
- CVE
- CVE-2026-16365
- Published
- Jul 21, 2026
- Updated
- Jul 21, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-284, CWE-269, T1068, T1203
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 21, 2026CVE publishedPublication date reported by the CVE source.
- Jul 21, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
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
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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