SB2021041620 - Red Hat Enterprise Linux 8.2 update for thunderbird
Published: April 16, 2021
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 3 secuirty vulnerabilities.
1) Cryptographic issues (CVE-ID: CVE-2021-23991)
The vulnerability allows a remote attacker to email encryption.
The vulnerability exists in the way Thunderbird uses the OpenPGP key refresh mechanism while handling the extended validity key period. A remote attacker can send victim an email containing a crafted version of the original key and an invalid subkey and force the application to use the invalid subkey, which will result in failure to encrypt the original email message when sending it.
2) Spoofing attack (CVE-ID: CVE-2021-23992)
The vulnerability allows a remote attacker to perform spoofing attack.
The vulnerability exists due to incorrect processing of user-supplied data, when checking if the user ID associated with an OpenPGP key has a valid self signature. An attacker may create a crafted version of an OpenPGP key, by either replacing the original user ID, or by adding another user ID. If Thunderbird imports and accepts the crafted key, the Thunderbird user may falsely conclude that the false user ID belongs to the correspondent.
3) Input validation error (CVE-ID: CVE-2021-23993)
The vulnerability allows a remote attacker to disable sending of encrypted messages.
The vulnerability exists due to insufficient validation of imported OpenPGP keys. A remote attacker can force the victim to import a specially crafted OpenPGO key with a subkey that has an invalid self signature and prevent users from sending encrypted messages to a correspondent.
Remediation
Install update from vendor's website.