CVE-2026-113866

Publication date 20 October 2026

Last updated 28 October 2026


Ubuntu priority

Cvss 3 Severity Score

5.9 · Medium

Score breakdown

Description

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.

Status

Package Ubuntu Release Status
thunderbird 26.10 stonking
Needs evaluation
26.04 LTS resolute
Needs evaluation
24.04 LTS noble
Needs evaluation
22.04 LTS jammy
Needs evaluation

Severity score breakdown

CVSS version: CVSS v3.0

Base score 5.9 · Medium

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N


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