Mozilla Firefox ESR < 78.9

critical Nessus Plugin ID 148012

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Synopsis

A web browser installed on the remote Windows host is affected by multiple vulnerabilities.

Description

The version of Firefox ESR installed on the remote Windows host is prior to 78.9. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2021-11 advisory.

- Mozilla developers and community members Alexis Beingessner, Tyson Smith, Julien Wajsberg, and Matthew Gregan reported memory safety bugs present in Firefox 86 and Firefox ESR 78.8. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. (CVE-2021-23987)

- An out of date graphics library (Angle) likely contained vulnerabilities that could potentially be exploited. (CVE-2021-4127)

- A transient execution vulnerability, named Floating Point Value Injection (FPVI) allowed an attacker to leak arbitrary memory addresses and may have also enabled JIT type confusion attacks. (A related vulnerability, Speculative Code Store Bypass (SCSB), did not affect Firefox.) (CVE-2021-29955)

- A texture upload of a Pixel Buffer Object could have confused the WebGL code to skip binding the buffer used to unpack it, resulting in memory corruption and a potentially exploitable information leak or crash.
(CVE-2021-23981)

- Using techniques that built on the slipstream research, a malicious webpage could have scanned both an internal network's hosts as well as services running on the user's local machine utilizing WebRTC connections. (CVE-2021-23982)

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 Firefox ESR version 78.9 or later.

Plugin Details

Severity: Critical

ID: 148012

File Name: mozilla_firefox_78_9_esr.nasl

Version: 1.7

Type: local

Agent: windows

Family: Windows

Published: 3/23/2021

Updated: 11/18/2025

Supported Sensors: Frictionless Assessment Agent, Frictionless Assessment AWS, Frictionless Assessment Azure, Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5.3

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

CVSS Score Source: CVE-2021-23987

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 8.8

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:P/RL:O/RC:C

CVSS Score Source: CVE-2021-4127

Vulnerability Information

CPE: cpe:/a:mozilla:firefox_esr

Required KB Items: installed_sw/Mozilla Firefox ESR

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 3/23/2021

Vulnerability Publication Date: 3/23/2021

Reference Information

CVE: CVE-2021-23981, CVE-2021-23982, CVE-2021-23984, CVE-2021-23987, CVE-2021-29955, CVE-2021-4127

IAVA: 2021-A-0144-S

Detections

Analytics