CVE-2026-57963: Vulnerability in Mozilla Thunderbird
CVE-2026-57963 is a vulnerability in Mozilla Thunderbird where 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 user interface. This issue was addressed and fixed in Thunderbird versions 140.12.1 and 152.0.1.
AI Analysis
Technical Summary
This vulnerability allows an attacker capable of sending HTML chat messages through Matrix or XMPP protocols to inject arbitrary styled content, including phishing links and CSS that can alter the chat UI in Mozilla Thunderbird. The flaw was resolved in Thunderbird versions 140.12.1 and 152.0.1, mitigating the risk of UI manipulation and phishing attacks via chat messages.
Potential Impact
An attacker exploiting this vulnerability could manipulate the chat interface by injecting styled content and phishing links, potentially deceiving users and facilitating phishing attacks. There is no indication of remote code execution or memory corruption from this vulnerability. No known exploits in the wild have been reported.
Mitigation Recommendations
This vulnerability has been fixed in Thunderbird versions 140.12.1 and 152.0.1. Users and administrators should upgrade to at least these versions to remediate the issue. No additional mitigation steps are indicated by the vendor advisory.
CVE-2026-57963: Vulnerability in Mozilla Thunderbird
Description
CVE-2026-57963 is a vulnerability in Mozilla Thunderbird where 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 user interface. This issue was addressed and fixed in Thunderbird versions 140.12.1 and 152.0.1.
Affected software
pkg:github/mozilla/thunderbirdRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability allows an attacker capable of sending HTML chat messages through Matrix or XMPP protocols to inject arbitrary styled content, including phishing links and CSS that can alter the chat UI in Mozilla Thunderbird. The flaw was resolved in Thunderbird versions 140.12.1 and 152.0.1, mitigating the risk of UI manipulation and phishing attacks via chat messages.
Potential Impact
An attacker exploiting this vulnerability could manipulate the chat interface by injecting styled content and phishing links, potentially deceiving users and facilitating phishing attacks. There is no indication of remote code execution or memory corruption from this vulnerability. No known exploits in the wild have been reported.
Mitigation Recommendations
This vulnerability has been fixed in Thunderbird versions 140.12.1 and 152.0.1. Users and administrators should upgrade to at least these versions to remediate the issue. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-06-26T15:27:32.832Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-62/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-63/","vendor":"Mozilla"}]
Threat ID: 6a446bac27e9c79719c2438f
Added to database: 07/01/2026, 01:21:48 UTC
Last enriched: 07/01/2026, 01:37:40 UTC
Last updated: 07/01/2026, 02:03:37 UTC
Views: 4
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