Unauthenticated DOM security mitigation bypass
Published Apr 21, 2026 · Updated Apr 21, 2026
Authentication bypass in Firefox before 150 and Thunderbird before 150 allows remote attackers to bypass a DOM security mitigation. Mozilla has not disclosed which DOM Security check is bypassed or which untrusted input reaches the alternate path; the linked bug remains access-restricted. The issue requires no authentication or user interaction, but Thunderbird disables scripting while reading email, limiting exposure to browser-like contexts.
Summary
What happened
Authentication bypass in Firefox before 150 and Thunderbird before 150 allows remote attackers to bypass a DOM security mitigation. Mozilla has not disclosed which DOM Security check is bypassed or which untrusted input reaches the alternate path; the linked bug remains access-restricted. The issue requires no authentication or user interaction, but Thunderbird disables scripting while reading email, limiting exposure to browser-like contexts.
The record
- CVE
- CVE-2026-6771
- Published
- Apr 21, 2026
- Updated
- Apr 21, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-288
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 21, 2026CVE publishedPublication date reported by the CVE source.
- Apr 21, 2026Record updatedLatest update available in the CVE record.
Exploitability
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What is affected?
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Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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