RHEL 8 : firefox (RHSA-2026:10766)

critical Nessus Plugin ID 310549

Synopsis

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

Description

The remote Redhat Enterprise Linux 8 host has a package installed that is affected by multiple vulnerabilities as referenced in the RHSA-2026:10766 advisory.

Mozilla Firefox is an open-source web browser, designed for standards compliance, performance, and portability.

Security Fix(es):

* firefox: thunderbird: Incorrect boundary conditions in the Libraries component in NSS (CVE-2026-6772)

* firefox: thunderbird: Use-after-free in the JavaScript Engine component (CVE-2026-6754)

* firefox: thunderbird: Spoofing issue in the DOM: Core & HTML component (CVE-2026-6762)

* firefox: thunderbird: Incorrect boundary conditions in the WebRTC component (CVE-2026-6752)

* firefox: thunderbird: Other issue in the Storage: IndexedDB component (CVE-2026-6770)

* firefox: thunderbird: Invalid pointer in the JavaScript: WebAssembly component (CVE-2026-6757)

* firefox: thunderbird: Other issue in the Libraries component in NSS (CVE-2026-6767)

* firefox: thunderbird: Memory safety bugs fixed in Firefox ESR 140.10, Thunderbird ESR 140.10, Firefox 150 and Thunderbird 150 (CVE-2026-6786)

* firefox: thunderbird: Incorrect boundary conditions in the WebRTC component (CVE-2026-6753)

* firefox: thunderbird: Use-after-free in the Widget: Cocoa component (CVE-2026-6759)

* firefox: thunderbird: Use-after-free in the WebRTC component (CVE-2026-6747)

* firefox: thunderbird: Information disclosure due to uninitialized memory in the Graphics: Canvas2D component (CVE-2026-6749)

* firefox: thunderbird: Incorrect boundary conditions in the Libraries component in NSS (CVE-2026-6766)

* firefox: thunderbird: Privilege escalation in the Networking component (CVE-2026-6761)

* firefox: thunderbird: Mitigation bypass in the File Handling component (CVE-2026-6763)

* firefox: thunderbird: Privilege escalation in the Graphics: WebRender component (CVE-2026-6750)

* firefox: thunderbird: Uninitialized memory in the Audio/Video: Web Codecs component (CVE-2026-6748)

* firefox: thunderbird: Memory safety bugs fixed in Firefox ESR 115.35, Firefox ESR 140.10, Thunderbird ESR 140.10, Firefox 150 and Thunderbird 150 (CVE-2026-6785)

* firefox: thunderbird: Mitigation bypass in the DOM: Security component (CVE-2026-6771)

* firefox: thunderbird: Incorrect boundary conditions in the DOM: Device Interfaces component (CVE-2026-6764)

* firefox: thunderbird: Information disclosure in the Form Autofill component (CVE-2026-6765)

* firefox: thunderbird: Privilege escalation in the Debugger component (CVE-2026-6769)

* firefox: thunderbird: Uninitialized memory in the Audio/Video: Web Codecs component (CVE-2026-6751)

* firefox: thunderbird: Incorrect boundary conditions in the WebRTC: Networking component (CVE-2026-6776)

* firefox: thunderbird: Use-after-free in the DOM: Core & HTML component (CVE-2026-6746)

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 firefox package based on the guidance in RHSA-2026:10766.

Plugin Details

Severity: Critical

ID: 310549

File Name: redhat-RHSA-2026-10766.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Red Hat Local Security Checks

Published: 4/27/2026

Updated: 4/27/2026

Supported Sensors: Nessus Agent, Continuous Assessment, Nessus

Risk Information

VPR

Risk Factor: High

Score: 7.4

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-2026-6771

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:/o:redhat:rhel_eus:8.10, cpe:/o:redhat:enterprise_linux:8, p-cpe:/a:redhat:enterprise_linux:firefox

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: 4/27/2026

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

CWE: 1021, 125, 131, 266, 358, 359, 440, 66, 676, 787, 805, 823, 824, 825

RHSA: 2026:10766

Detections

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