vulnerability

Ubuntu: (Multiple Advisories) (CVE-2021-23993): Thunderbird vulnerabilities

Severity
4
CVSS
(AV:N/AC:M/Au:N/C:N/I:P/A:N)
Published
Apr 15, 2021
Added
Jun 23, 2021
Modified
Aug 18, 2025

Description

An attacker may perform a DoS attack to prevent a user from sending encrypted email to a correspondent. If an attacker creates a crafted OpenPGP key with a subkey that has an invalid self signature, and the Thunderbird user imports the crafted key, then Thunderbird may try to use the invalid subkey, but the RNP library rejects it from being used, causing encryption to fail. This vulnerability affects Thunderbird < 78.9.1.

Solution

ubuntu-upgrade-thunderbird
Title
NEW

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