SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-57962

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.

MEDIUM 5.3EPSS 0.22%

Does this matter?

Lower severity and a low EPSS score (0.22%). Track it; it rarely justifies an emergency change on its own.

Description

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.

CVSS 3.1
5.3 MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H
EPSS
0.22% probability · 13th percentile
CISA KEV
Not listed
Weakness
CWE-400
Affected
mozilla/thunderbird
Source
security@mozilla.org

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