RHEL 9 : thunderbird (RHSA-2026:85241)

critical Nessus Plugin ID 371628

Synopsis

The remote Red Hat host is missing one or more security updates for thunderbird.

Description

The remote Redhat Enterprise Linux 9 host has a package installed that is affected by multiple vulnerabilities as referenced in the RHSA-2026:85241 advisory.

Mozilla Thunderbird is a standalone mail and newsgroup client.

Security Fix(es):

* firefox: thunderbird: Use-after-free in the Graphics: Canvas2D component (CVE-2026-100832)

* firefox: Use-after-free in the Layout: Text and Fonts component (CVE-2026-100784)

* firefox: thunderbird: Privilege escalation in the DLL Services component (CVE-2026-100801)

* firefox: thunderbird: Sandbox escape due to incorrect boundary conditions in the Internationalization component (CVE-2026-100794)

* firefox: thunderbird: Privilege escalation in the Address Bar component (CVE-2026-100820)

* firefox: thunderbird: Use-after-free in the Graphics: Canvas2D component (CVE-2026-100777)

* firefox: thunderbird: Information disclosure in the Networking: JAR component (CVE-2026-100766)

* firefox: thunderbird: Use-after-free in the XSLT component (CVE-2026-100779)

* firefox: thunderbird: Privilege escalation in the DOM: Service Workers component (CVE-2026-100807)

* firefox: thunderbird: JIT miscompilation in the JavaScript: WebAssembly component (CVE-2026-100792)

* firefox: Privilege escalation due to use-after-free in the Graphics: WebRender component (CVE-2026-100797)

* firefox: thunderbird: Sandbox escape due to incorrect boundary conditions in the XPCOM component (CVE-2026-100819)

* firefox: thunderbird: Use-after-free in the JavaScript: WebAssembly component (CVE-2026-100776)

* firefox: thunderbird: Use-after-free in the Widget component (CVE-2026-100757)

* firefox: Sandbox escape due to use-after-free in the Graphics component (CVE-2026-100786)

* firefox: thunderbird: Information disclosure in the Networking component (CVE-2026-96869)

* firefox: Sandbox escape due to use-after-free in the DOM: Content Processes component (CVE-2026-100770)

* firefox: thunderbird: Use-after-free in the JavaScript: WebAssembly component (CVE-2026-100769)

* firefox: Use-after-free in the DOM: Core & HTML component (CVE-2026-100791)

* firefox: thunderbird: Sandbox escape due to use-after-free in the Widget: Gtk component (CVE-2026-100818)

* firefox: thunderbird: Privilege escalation due to incorrect boundary conditions in the Graphics component (CVE-2026-100782)

* firefox: firefox: Sandbox escape via use-after-free in DOM component (CVE-2026-100811)

* firefox: thunderbird: Use-after-free in the DOM: Core & HTML component (CVE-2026-100772)

* firefox: thunderbird: Uninitialized memory in the Storage: Quota Manager component (CVE-2026-100759)

* firefox: Sandbox escape due to use-after-free in the DOM: Core & HTML component (CVE-2026-100778)

* firefox: thunderbird: Sandbox escape in the DOM: Navigation component (CVE-2026-100758)

* firefox: thunderbird: Sandbox escape in the Graphics component (CVE-2026-100775)

* firefox: thunderbird: Sandbox escape due to incorrect boundary conditions in the Graphics: WebRender component (CVE-2026-100781)

* firefox: Use-after-free in the DOM: Core & HTML component (CVE-2026-100774)

* firefox: thunderbird: Same-origin policy bypass in the WebExtensions component (CVE-2026-100803)

* firefox: thunderbird: Use-after-free in the Graphics: Canvas2D component (CVE-2026-100789)

* firefox: thunderbird: Use-after-free in the DOM: Core & HTML component (CVE-2026-100785)

* firefox: thunderbird: Site isolation issue in the Panning and Zooming component (CVE-2026-100821)

* firefox: thunderbird: Invalid pointer in the JavaScript: WebAssembly component (CVE-2026-100788)

* firefox: thunderbird: Undefined behavior in the DOM: Streams component (CVE-2026-100771)

* firefox: Sandbox escape due to use-after-free in the DOM: Content Processes component (CVE-2026-100762)

* firefox: thunderbird: Use-after-free in the XSLT component (CVE-2026-100790)

* firefox: thunderbird: Use-after-free in the Storage: IndexedDB component (CVE-2026-100773)

* firefox: thunderbird: Use-after-free in the DOM: Core & HTML component (CVE-2026-100780)

* firefox: thunderbird: Use-after-free in the Networking: Cache component (CVE-2026-100767)

* firefox: thunderbird: Incorrect boundary conditions in the Audio/Video: Playback component (CVE-2026-100756)

* firefox: thunderbird: Uninitialized memory in the Audio/Video component (CVE-2026-100783)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux 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

Update the RHEL thunderbird package based on the guidance in RHSA-2026:85241.

Plugin Details

Severity: Critical

ID: 371628

File Name: redhat-RHSA-2026-85241.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Red Hat Local Security Checks

Published: 10/23/2026

Updated: 10/23/2026

Supported Sensors: Nessus Agent, Continuous Assessment, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 5

Percentile: 93.16

Vendor

Vendor Severity: Important

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-2026-100832

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

CVSS Score Source: CVE-2026-100788

Vulnerability Information

CPE: cpe:/o:redhat:rhel_e4s:9.4, p-cpe:/a:redhat:enterprise_linux:thunderbird

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

Exploit Ease: No known exploits are available

Patch Publication Date: 10/19/2026

Vulnerability Publication Date: 9/29/2026

Reference Information

CVE: CVE-2026-100756, CVE-2026-100757, CVE-2026-100758, CVE-2026-100759, CVE-2026-100762, CVE-2026-100766, CVE-2026-100767, CVE-2026-100769, CVE-2026-100770, CVE-2026-100771, CVE-2026-100772, CVE-2026-100773, CVE-2026-100774, CVE-2026-100775, CVE-2026-100776, CVE-2026-100777, CVE-2026-100778, CVE-2026-100779, CVE-2026-100780, CVE-2026-100781, CVE-2026-100782, CVE-2026-100783, CVE-2026-100784, CVE-2026-100785, CVE-2026-100786, CVE-2026-100788, CVE-2026-100789, CVE-2026-100790, CVE-2026-100791, CVE-2026-100792, CVE-2026-100794, CVE-2026-100797, CVE-2026-100801, CVE-2026-100803, CVE-2026-100807, CVE-2026-100811, CVE-2026-100818, CVE-2026-100819, CVE-2026-100820, CVE-2026-100821, CVE-2026-100832, CVE-2026-96869

CWE: 119, 15, 200, 201, 269, 284, 346, 416, 457, 693, 758, 824, 825, 843, 908

RHSA: 2026:85241

Detections

Analytics