CVE-2020-15646

Severity: medium (CVSS 5.9 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.0% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-10-08 · updated 2026-06-17

Description

If an attacker intercepts Thunderbird's initial attempt to perform automatic account setup using the Microsoft Exchange autodiscovery mechanism, and the attacker sends a crafted response, then Thunderbird sends username and password over https to a server controlled by the attacker. This vulnerability affects Thunderbird < 68.10.0.

Affected products

Mozilla Thunderbird: before 68.10.0 — fixed in 68.10.0

How to fix

Upgrade to a fixed version: Mozilla Thunderbird 68.10.0. Check the vendor advisory for mitigations.

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1606610
https://www.mozilla.org/security/advisories/mfsa2020-26/
https://bugzilla.mozilla.org/show_bug.cgi?id=1606610
https://www.mozilla.org/security/advisories/mfsa2020-26/

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