Security-control bypass in Service Workers
Published Jul 21, 2026 · Updated Jul 21, 2026
Mitigation bypass in Mozilla Firefox and Thunderbird before 153 allows attackers to bypass a Service Workers security control. The public advisories name only the DOM: Service Workers component; Mozilla's linked bug is access-restricted and the flawed operation is undisclosed. Thunderbird generally blocks exploitation through email because scripting is disabled while reading messages, and Mozilla has not published the security consequence beyond mitigation bypass.
Summary
What happened
Mitigation bypass in Mozilla Firefox and Thunderbird before 153 allows attackers to bypass a Service Workers security control. The public advisories name only the DOM: Service Workers component; Mozilla's linked bug is access-restricted and the flawed operation is undisclosed. Thunderbird generally blocks exploitation through email because scripting is disabled while reading messages, and Mozilla has not published the security consequence beyond mitigation bypass.
The record
- CVE
- CVE-2026-16382
- Published
- Jul 21, 2026
- Updated
- Jul 21, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-693
- 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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What is affected?
Affected products and versions are unavailable in this record.
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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