CVE-2026-113866
Account password sent unencrypted during Exchange account setup
- State
- Published
- Severity
- 5.9 Medium
- Published
- Oct 20, 2026
- Updated
- Oct 20, 2026
- Reserved
- Oct 20, 2026
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 5.9 Medium | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N | CISA-ADP |
Weaknesses
- CWE-523 Unprotected Transport of Credentials
Affected Products
| Product | Versions |
|---|---|
ThunderbirdMozilla |
|
References
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