Bug 2495814 (CVE-2026-57963)

Summary: CVE-2026-57963 thunderbird: Chat UI manipulation by injection
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: gotiwari, jhorak, mvyas, rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue: 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.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-07-01 02:01:27 UTC
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.