Vulnerability 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.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Mozilla | Thunderbird | < 78.9.1 |
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=1673240ExploitIssue TrackingVendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2021-13/Release NotesVendor Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=1673240ExploitIssue TrackingVendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2021-13/Release NotesVendor Advisory
FAQ
What is CVE-2021-23991?
CVE-2021-23991 is a vulnerability with a CVSS score of 6.8 (MEDIUM). 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 ema...
How severe is CVE-2021-23991?
CVE-2021-23991 has been rated MEDIUM with a CVSS base score of 6.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2021-23991?
Check the references section above for vendor advisories and patch information. Affected products include: Mozilla Thunderbird.