Detections
Analytics

Mozilla Thunderbird < 140.12.1

medium Nessus Plugin ID 324037

Synopsis

A mail client installed on the remote macOS or Mac OS X host is affected by multiple vulnerabilities.

Description

The version of Thunderbird installed on the remote macOS or Mac OS X host is prior to 140.12.1. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2026-63 advisory.

 - An attacker who can send HTML chat messages (via Matrix or XMPP) can inject arbitrary styled content, phishing links, and CSS that manipulates the chat UI. (CVE-2026-57963)

 - 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. (CVE-2026-57962)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Solution

Upgrade to Mozilla Thunderbird version 140.12.1 or later.

See Also

https://www.mozilla.org/en-US/security/advisories/mfsa2026-63/

Plugin Details

Severity: Medium

ID: 324037

File Name: macos_thunderbird_140_12_1.nasl

Version: 1.1

Type: Local

Agent: macosx

Published: 7/1/2026

Updated: 7/1/2026

Supported Sensors: Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3

Percentile: 23.72

CVSS v2

Risk Factor: Medium

Base Score: 5

Temporal Score: 3.7

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:P/A:N

CVSS Score Source: CVE-2026-57963

CVSS v3

Risk Factor: Medium

Base Score: 5.4

Temporal Score: 4.7

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/a:mozilla:thunderbird

Required KB Items: installed_sw/Mozilla Thunderbird

Exploit Ease: No known exploits are available

Patch Publication Date: 6/30/2026

Vulnerability Publication Date: 6/30/2026

Reference Information

CVE: CVE-2026-57962, CVE-2026-57963