#VU59081 Insufficient UI Warning of Dangerous Operations in Mozilla Thunderbird

Published: 2021-12-21

Vulnerability identifier: #VU59081

Vulnerability risk: Low


CVE-ID: CVE-2021-4126


Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Mozilla Thunderbird
Client/Desktop applications / Messaging software

Vendor: Mozilla


The vulnerability allows a remote attacker to perform spoofing attacks.

The vulnerability exists in the way Thunderbird handles signed email messages. When receiving an OpenPGP/MIME signed email message that contains an additional outer MIME message layer, for example a message footer added by a mailing list gateway, Thunderbird only considered the inner signed message for the signature validity. This gave the false impression that the additional contents were also covered by the digital signature.

Install updates from vendor's website.

Vulnerable software versions

Mozilla Thunderbird: 91.0 - 91.4.0


External links

Q & A

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