MEDIUMCVSS 5.9
CVE-2026-113866
CVE-2026-113866 updated by NVD
Summary
When setting up an account, Thunderbird's Exchange AutoDiscover lookup also queried the domain's AutoDiscover service over plain HTTP. Due to a bug, that unencrypted request included the credentials the user had entered, allowing a network attacker to obtain the user's password. This vulnerability was fixed in Thunderbird 158.0.1 and Thunderbird 153.5.1.
References
Includes data from the National Vulnerability Database (NIST). NVD data is in the public domain; this page is not endorsed by NIST.
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