Firefox Popup Blocker Spoofing Vulnerability (CVE-2026-8964)
CVE-2026-8964 Published on May 19, 2026
Spoofing issue in the Popup Blocker component
Spoofing issue in the Popup Blocker component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.
Vulnerability Analysis
CVE-2026-8964 is exploitable with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality, a high impact on integrity, and no impact on availability.
Weakness Type
User Interface (UI) Misrepresentation of Critical Information
The user interface (UI) does not properly represent critical information to the user, allowing the information - or its source - to be obscured or spoofed. This is often a component in phishing attacks.
Products Associated with CVE-2026-8964
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Affected Versions
Mozilla Firefox:- Version 151, <= * is unaffected.
- Version 151, <= * is unaffected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.