PT-2026-54448 · Mozilla · Thunderbird

Michael Bommarito

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Published

2026-07-01

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Updated

2026-07-01

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CVE-2026-57963

None

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An attacker who can send HTML chat messages (via Matrix or XMPP) can inject arbitrary styled content, phishing links, and CSS that manipulates the chat UI. This vulnerability was fixed in Thunderbird 152.0.1 and Thunderbird 140.12.1.
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Related Identifiers

CVE-2026-57963

Affected Products

Thunderbird