VULNERABILITY INTELLIGENCE
CVE-2021-23991
CVSS score6.8 MEDIUM
EPSS probability1.03%
CISA KEVNot currently listed
Published2021-06-24
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
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.
Weakness classification
- nvd@nist.gov: NVD-CWE-Other
Primary references
- security@mozilla.org — Exploit, Issue Tracking, Vendor Advisory
- security@mozilla.org — Release Notes, Vendor Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Exploit, Issue Tracking, Vendor Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Release Notes, Vendor Advisory