A malicious LDAP server, which a Thunderbird user is configured to query for address-book autocomplete, can stash arbitrarily large amounts of attacker-supplied data into the Thunderbird LDAP client until it crashes due to memory exhaustion. This vulnerability was fixed in Thunderbird 152.0.1 and Thunderbird 140.12.1.
Exploitability
AV:NAC:HPR:NUI:RScope
S:UImpact
C:NI:NA:H5.3/CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H