vulnerability
MFSA2021-13 Thunderbird: Security Vulnerabilities fixed in Thunderbird 78.9.1 (CVE-2021-23991)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 4 | (AV:N/AC:H/Au:N/C:P/I:P/A:N) | Apr 8, 2021 | Apr 9, 2021 | Mar 27, 2026 |
Severity
4
CVSS
(AV:N/AC:H/Au:N/C:P/I:P/A:N)
Published
Apr 8, 2021
Added
Apr 9, 2021
Modified
Mar 27, 2026
Description
If a Thunderbird user has previously imported Alice's OpenPGP key, and Alice has extended the validity period of her key, but Alice's updated key has not yet been imported, an attacker may send an email containing a crafted version of Alice's key with an invalid subkey, Thunderbird might subsequently attempt to use the invalid subkey, and will fail to send encrypted email to Alice. This vulnerability affects Thunderbird < 78.9.1.
Solution
mozilla-thunderbird-upgrade-78_9_1
Rapid7 Labs
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