Mozilla Thunderbird < 159.0

high Nessus Plugin ID 372628

Synopsis

A mail client installed on the remote Windows host is affected by multiple vulnerabilities.

Description

The version of Thunderbird installed on the remote Windows host is prior to 159.0. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2026-121 advisory.

- Privilege escalation in the DOM: Navigation component. This vulnerability was fixed in Firefox 159.
(CVE-2026-118008)

- When a message containing an OpenPGP key attachment was displayed, Thunderbird automatically loaded the attachment's content to offer importing the key. A sender could mark the attachment as an external attachment pointing to an arbitrary URL, which Thunderbird then loaded without any user interaction, bypassing remote content blocking. On Windows, a URL pointing to an attacker-controlled network share could leak the user's NTLM credentials. The NTLM credential leak only affects Thunderbird on Windows. On other operating systems, the issue allowed a remote request that bypassed remote content blocking.
(CVE-2026-118174)

- When replying to, forwarding, or editing a crafted email message as new, Thunderbird could embed parts of a different message stored in the same folder into the message being composed, without showing a blocked content warning. If the user sent the message, the content of the other message was disclosed to the recipients. (CVE-2026-118175)

- Thunderbird's check that prevents mailbox: URLs from accessing files on remote Windows network shares could be bypassed using extended-length UNC paths. Displaying a specially crafted email could cause Thunderbird to connect to an SMB server chosen by the attacker, disclosing the user's Windows account name and NTLM authentication data, which could be used for offline password cracking or relay attacks. This bug only affects Thunderbird on Windows. Other operating systems are unaffected. (CVE-2026-118176)

- When looking for calendars in a directory on a server, during account setup or when adding a new network calendar, Thunderbird accepted calendar locations pointing to other servers, local files or network shares. A malicious server, or a network attacker when the lookup used plain HTTP, could make Thunderbird subscribe to such a location. On Windows this could leak the user's NTLM credentials to an attacker- controlled host on every calendar refresh, and changes to the calendar could be written to the attacker's share or overwrite a local file. (CVE-2026-118177)

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 159.0 or later.

See Also

https://www.mozilla.org/en-US/security/advisories/mfsa2026-121/

Plugin Details

Severity: High

ID: 372628

File Name: mozilla_thunderbird_159_0.nasl

Version: 1.1

Type: Local

Agent: windows

Family: Windows

Published: 10/27/2026

Updated: 10/27/2026

Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Azure, Frictionless Assessment Agent, Nessus Agent, Tenable Cloud Security, Tenable Self-Hosted Container Security, Nessus

Risk Information

VPR

Risk Factor: High

Score: 7

Percentile: 97.98

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-2026-118008

CVSS v3

Risk Factor: High

Base Score: 8.8

Temporal Score: 7.7

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/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: 10/27/2026

Vulnerability Publication Date: 9/29/2026

Reference Information

CVE: CVE-2026-100801, CVE-2026-117860, CVE-2026-117861, CVE-2026-117862, CVE-2026-117863, CVE-2026-117864, CVE-2026-117865, CVE-2026-117866, CVE-2026-117867, CVE-2026-117868, CVE-2026-117869, CVE-2026-117870, CVE-2026-117871, CVE-2026-117872, CVE-2026-117873, CVE-2026-117874, CVE-2026-117875, CVE-2026-117876, CVE-2026-117877, CVE-2026-117878, CVE-2026-117879, CVE-2026-117880, CVE-2026-117881, CVE-2026-117882, CVE-2026-117883, CVE-2026-117884, CVE-2026-117885, CVE-2026-117886, CVE-2026-117887, CVE-2026-117888, CVE-2026-117889, CVE-2026-117890, CVE-2026-117891, CVE-2026-117892, CVE-2026-117893, CVE-2026-117894, CVE-2026-117895, CVE-2026-117896, CVE-2026-117897, CVE-2026-117898, CVE-2026-117899, CVE-2026-117900, CVE-2026-117901, CVE-2026-117902, CVE-2026-117903, CVE-2026-117904, CVE-2026-117905, CVE-2026-117906, CVE-2026-117907, CVE-2026-117908, CVE-2026-117909, CVE-2026-117910, CVE-2026-117911, CVE-2026-117912, CVE-2026-117913, CVE-2026-117914, CVE-2026-117915, CVE-2026-117916, CVE-2026-117917, CVE-2026-117918, CVE-2026-117919, CVE-2026-117920, CVE-2026-117921, CVE-2026-117922, CVE-2026-117923, CVE-2026-117924, CVE-2026-117925, CVE-2026-117926, CVE-2026-117927, CVE-2026-117928, CVE-2026-117929, CVE-2026-117930, CVE-2026-117931, CVE-2026-117932, CVE-2026-117933, CVE-2026-117934, CVE-2026-117935, CVE-2026-117936, CVE-2026-117937, CVE-2026-117938, CVE-2026-117939, CVE-2026-117940, CVE-2026-117941, CVE-2026-117942, CVE-2026-117943, CVE-2026-117944, CVE-2026-117945, CVE-2026-117946, CVE-2026-117947, CVE-2026-117948, CVE-2026-117949, CVE-2026-117950, CVE-2026-117951, CVE-2026-117952, CVE-2026-117953, CVE-2026-117954, CVE-2026-117955, CVE-2026-117956, CVE-2026-117957, CVE-2026-117958, CVE-2026-117959, CVE-2026-117960, CVE-2026-117961, CVE-2026-117962, CVE-2026-117963, CVE-2026-117964, CVE-2026-117965, CVE-2026-117966, CVE-2026-117967, CVE-2026-117968, CVE-2026-117969, CVE-2026-117970, CVE-2026-117971, CVE-2026-117972, CVE-2026-117973, CVE-2026-117974, CVE-2026-117975, CVE-2026-117976, CVE-2026-117977, CVE-2026-117978, CVE-2026-117979, CVE-2026-117980, CVE-2026-117981, CVE-2026-117982, CVE-2026-117983, CVE-2026-117984, CVE-2026-117985, CVE-2026-117986, CVE-2026-117987, CVE-2026-117988, CVE-2026-117989, CVE-2026-117990, CVE-2026-117991, CVE-2026-117992, CVE-2026-117993, CVE-2026-117994, CVE-2026-117995, CVE-2026-117996, CVE-2026-117997, CVE-2026-117998, CVE-2026-117999, CVE-2026-118000, CVE-2026-118002, CVE-2026-118003, CVE-2026-118004, CVE-2026-118005, CVE-2026-118006, CVE-2026-118007, CVE-2026-118008, CVE-2026-118009, CVE-2026-118010, CVE-2026-118011, CVE-2026-118012, CVE-2026-118013, CVE-2026-118014, CVE-2026-118015, CVE-2026-118016, CVE-2026-118017, CVE-2026-118019, CVE-2026-118020, CVE-2026-118021, CVE-2026-118022, CVE-2026-118023, CVE-2026-118024, CVE-2026-118025, CVE-2026-118026, CVE-2026-118174, CVE-2026-118175, CVE-2026-118176, CVE-2026-118177, CVE-2026-118178, CVE-2026-118179, CVE-2026-118180