Amazon Linux 2 : thunderbird (ALAS-2026-3952)

critical Nessus Plugin ID 351035

Synopsis

The remote Amazon Linux 2 host is missing a security update.

Description

The version of thunderbird installed on the remote host is prior to 140.16.0-1. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2-2026-3952 advisory.

Triggering an error condition in certain MIME bodies would cause uninitialized memory to be used. This vulnerability was fixed in Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2. (CVE-2026-84639)

A maliciously constructed mail header could lead to a one byte read past the end of a buffer. This vulnerability was fixed in Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2. (CVE-2026-84640)

A malicious IMAP server can trigger use-after-free and heap-memory disclosure by sending a crafted ID response. Heap contents can ultimately be persisted to prefs.js. This vulnerability was fixed in Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2. (CVE-2026-84641)

Privilege escalation due to incorrect boundary conditions in the Graphics component. This vulnerability was fixed in Firefox ESR 115.41, Firefox ESR 140.16, and Thunderbird 140.16. (CVE-2026-92014)

Privilege escalation in the DOM: Service Workers component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, and Firefox ESR 153.3. (CVE-2026-92017)

Use-after-free in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox ESR 140.16 and Thunderbird 140.16. (CVE-2026-92021)

A maliciously constructed mail header could lead to multiple fields being parsed as one, or potential memory safety violations. This vulnerability was fixed in Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3. (CVE-2026-92238)

A maliciously constructed IMAP line could cause an out-of-bounds buffer read. This vulnerability was fixed in Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3. (CVE-2026-92239)

A malicious or compromised IMAP server can trigger an out-of-bounds read in the IMAP response parser by sending an untagged '* ID' response, crashing Thunderbird. The affected parsing path is reachable before authentication. This vulnerability was fixed in Thunderbird 156 and Thunderbird 140.16. (CVE-2026-92240)

Tenable has extracted the preceding description block directly from the tested product security advisory.

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

Solution

Run 'yum update thunderbird' or or 'yum update --advisory ALAS2-2026-3952' to update your system.

Plugin Details

Severity: Critical

ID: 351035

File Name: al2_ALAS-2026-3952.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Amazon Linux Local Security Checks

Published: 9/29/2026

Updated: 9/29/2026

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

Risk Information

VPR

Risk Factor: Medium

Score: 4.9

Percentile: 58.29

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-2026-92238

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:/o:amazon:linux:2, p-cpe:/a:amazon:linux:thunderbird

Required KB Items: Host/local_checks_enabled, Host/AmazonLinux/release, Host/AmazonLinux/rpm-list

Exploit Ease: No known exploits are available

Patch Publication Date: 9/28/2026

Vulnerability Publication Date: 9/1/2026

Reference Information

CVE: CVE-2026-84639, CVE-2026-84640, CVE-2026-84641, CVE-2026-92014, CVE-2026-92017, CVE-2026-92021, CVE-2026-92238, CVE-2026-92239, CVE-2026-92240

IAVA: 2026-A-0929-S, 2026-A-1017

Detections

Analytics