Detections
Analytics

Mozilla Thunderbird < 140.10

critical Nessus Plugin ID 309101

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 140.10. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2026-34 advisory.

 - Mitigation bypass in the DOM: Security component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10. (CVE-2026-6771)

 - Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 150, Firefox ESR 115.35, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10. (CVE-2026-6746)

 - Use-after-free in the WebRTC component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10. (CVE-2026-6747)

 - Uninitialized memory in the Audio/Video: Web Codecs component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10. (CVE-2026-6748, CVE-2026-6751)

 - Information disclosure due to uninitialized memory in the Graphics: Canvas2D component. This vulnerability was fixed in Firefox 150, Firefox ESR 115.35, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.
 (CVE-2026-6749)

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 140.10 or later.

See Also

https://www.mozilla.org/en-US/security/advisories/mfsa2026-34/

Plugin Details

Severity: Critical

ID: 309101

File Name: macos_thunderbird_140_10.nasl

Version: 1.1

Type: Local

Agent: macosx

Published: 4/21/2026

Updated: 4/21/2026

Supported Sensors: Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: High

Score: 8.4

CVSS v2

Risk Factor: Critical

Base Score: 10

Temporal Score: 7.4

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

CVSS Score Source: CVE-2026-6771

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 8.5

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

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: 4/21/2026

Vulnerability Publication Date: 4/21/2026

Reference Information

CVE: CVE-2026-6746, CVE-2026-6747, CVE-2026-6748, CVE-2026-6749, CVE-2026-6750, CVE-2026-6751, CVE-2026-6752, CVE-2026-6753, CVE-2026-6754, CVE-2026-6757, CVE-2026-6759, CVE-2026-6761, CVE-2026-6762, CVE-2026-6763, CVE-2026-6764, CVE-2026-6765, CVE-2026-6766, CVE-2026-6767, CVE-2026-6769, CVE-2026-6770, CVE-2026-6771, CVE-2026-6772, CVE-2026-6776, CVE-2026-6785, CVE-2026-6786