SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2021-23991

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…

MEDIUM 6.8EPSS 1.03%

Does this matter?

Lower severity and a low EPSS score (1.03%). Track it; it rarely justifies an emergency change on its own.

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 3.1
6.8 MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
EPSS
1.03% probability · 62th percentile
CISA KEV
Not listed
Affected
mozilla/thunderbird
Source
security@mozilla.org

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.