Vulnerability in Mozilla Thunderbird

CVE-2021-23992

Thunderbird did not check 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. This vulnerability affects Thunderbird < 78.9.1.

EPSS: 0.005 (38.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-23992?
CVE-2021-23992 is a medium-severity vulnerability in Mozilla Thunderbird, classified under Improper Verification of Cryptographic Signature. CVSS score: 4.3/10. Published 2021-06-24.
How severe is CVE-2021-23992?
Medium severity. CVSS v3 base score is 4.3 out of 10.
Is CVE-2021-23992 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.