vulnerability

Oracle Linux: CVE-2021-23993: ELSA-2021-1192: thunderbird security update (MODERATE) (Multiple Advisories)

Severity
4
CVSS
(AV:N/AC:M/Au:N/C:N/I:P/A:N)
Published
Apr 8, 2021
Added
Apr 15, 2021
Modified
Dec 3, 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

oracle-linux-upgrade-thunderbird
Title
Rapid7 Labs

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