Mitigation Bypass in Firefox Popup Blocker (before 156)
CVE-2026-92074 Published on September 15, 2026
Mitigation bypass in the Popup Blocker component
Mitigation bypass in the Popup Blocker component. This vulnerability was fixed in Firefox 156, Firefox ESR 153.3, Thunderbird 156, and Thunderbird 153.3.
Vulnerability Analysis
CVE-2026-92074 is exploitable with local system access, and requires small amount of user privileges. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to be very high.
Weakness Type
Protection Mechanism Failure
The product does not use or incorrectly uses a protection mechanism that provides sufficient defense against directed attacks against the product. This weakness covers three distinct situations. A "missing" protection mechanism occurs when the application does not define any mechanism against a certain class of attack. An "insufficient" protection mechanism might provide some defenses - for example, against the most common attacks - but it does not protect against everything that is intended. Finally, an "ignored" mechanism occurs when a mechanism is available and in active use within the product, but the developer has not applied it in some code path.
Products Associated with CVE-2026-92074
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Affected Versions
Mozilla Firefox:- Version 153.3, <= 153.* is unaffected.
- Version 156, <= * is unaffected.
- Version 153.3, <= 153.* is unaffected.
- Version 156, <= * is unaffected.