Skip to main content

Firefox Esr CVE-2026-4687

| EUVDEUVD-2026-14798 HIGH
Improper Check for Unusual or Exceptional Conditions (CWE-754)
2026-03-24 mozilla
8.6
CVSS 3.1 · NVD
Share

Severity by source

NVD PRIMARY
8.6 HIGH
AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
SUSE
9.6 CRITICAL
AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
Red Hat
7.5 HIGH
qualitative

Primary rating from NVD.

CVSS VectorNVD

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Changed
Confidentiality
None
Integrity
None
Availability
High

Lifecycle Timeline

4
Patch released
Mar 31, 2026 - 21:13 nvd
Patch available
EUVD ID Assigned
Mar 24, 2026 - 12:45 euvd
EUVD-2026-14798
Analysis Generated
Mar 24, 2026 - 12:45 vuln.today
CVE Published
Mar 24, 2026 - 12:30 nvd
HIGH 8.6

DescriptionNVD

Sandbox escape due to incorrect boundary conditions in the Telemetry component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, and Firefox ESR < 140.9.

AnalysisAI

A sandbox escape vulnerability exists in Firefox's Telemetry component due to incorrect boundary condition handling, allowing attackers to potentially break out of the browser sandbox and access system resources or sensitive data. This affects Firefox versions below 149, Firefox ESR below 115.34, and Firefox ESR below 140.9. The vulnerability enables information disclosure and potentially arbitrary code execution by circumventing the sandbox isolation mechanism that normally restricts browser processes.

Technical ContextAI

The vulnerability resides in the Telemetry component of Mozilla Firefox, a core telemetry collection system responsible for gathering anonymized usage data and crash reports. The root cause is classified as an incorrect boundary condition (implied CWE-119 or similar bounds-checking defect), where the Telemetry component fails to properly validate memory or privilege boundaries when processing telemetry data. The affected products are identified via CPE strings: cpe:2.3:a:mozilla:firefox (all versions), cpe:2.3:a:mozilla:firefox_esr (all versions), indicating both the mainline Firefox and Extended Support Release branches are impacted. The Telemetry system operates with elevated privileges within the browser process, making boundary condition flaws particularly dangerous as they can serve as a pivot point for sandbox escape attacks.

RemediationAI

Upgrade Firefox to version 149 or later immediately; upgrade Firefox ESR to version 115.34 or version 140.9 or later depending on your ESR channel. Users should enable automatic updates in Firefox preferences (Settings > General > Firefox Updates > Automatic) to receive patches as soon as they are released. Organizations managing Firefox deployments should use Mozilla's official security advisories at https://www.mozilla.org/security/advisories/ to coordinate patching across their infrastructure. Until patching is complete, consider blocking access to untrusted websites via content filtering or restricting browser usage to internal, trusted sites. Do not attempt to apply workarounds at the OS level, as sandbox escapes by definition defeat such boundaries; patching Firefox itself is the only reliable mitigation.

CVE-2020-26950 HIGH POC
8.8 Dec 09

In certain circumstances, the MCallGetProperty opcode can be emitted with unmet assumptions resulting in an exploitable

CVE-2026-4689 CRITICAL POC
10.0 Mar 24

A sandbox escape vulnerability exists in Firefox's XPCOM component due to incorrect boundary conditions and integer over

CVE-2022-29917 CRITICAL POC
9.8 Dec 22

Mozilla developers Andrew McCreight, Gabriele Svelto, Tom Ritter and the Mozilla Fuzzing Team reported memory safety bug

CVE-2014-1568 HIGH
7.5 Sep 25

Mozilla Network Security Services (NSS) before 3.16.2.1, 3.16.x before 3.16.5, and 3.17.x before 3.17.1, as used in Mozi

CVE-2022-26384 CRITICAL POC
9.6 Dec 22

If an attacker could control the contents of an iframe sandboxed with <code>allow-popups</code> but not <code>allow-scri

CVE-2022-34484 HIGH POC
8.8 Dec 22

The Mozilla Fuzzing Team reported potential vulnerabilities present in Thunderbird 91.10. Rated high severity (CVSS 8.8)

CVE-2022-28281 HIGH POC
8.8 Dec 22

If a compromised content process sent an unexpected number of WebAuthN Extensions in a Register command to the parent pr

CVE-2022-26381 HIGH POC
8.8 Dec 22

An attacker could have caused a use-after-free by forcing a text reflow in an SVG object leading to a potentially exploi

CVE-2022-22756 HIGH POC
8.8 Dec 22

If a user was convinced to drag and drop an image to their desktop or other folder, the resulting object could have been

CVE-2022-22740 HIGH POC
8.8 Dec 22

Certain network request objects were freed too early when releasing a network request handle. Rated high severity (CVSS

CVE-2022-22738 HIGH POC
8.8 Dec 22

Applying a CSS filter effect could have accessed out of bounds memory. Rated high severity (CVSS 8.8), this vulnerabilit

CVE-2021-29988 HIGH POC
8.8 Aug 17

Firefox incorrectly treated an inline list-item element as a block element, resulting in an out of bounds read or memory

Vendor StatusVendor

Debian

firefox
Release Status Fixed Version Urgency
sid vulnerable 148.0.2-1 -
(unstable) fixed (unfixed) -
firefox-esr
Release Status Fixed Version Urgency
bullseye vulnerable 115.14.0esr-1~deb11u1 -
bullseye (security) vulnerable 140.8.0esr-1~deb11u1 -
bookworm vulnerable 128.14.0esr-1~deb12u1 -
bookworm (security) vulnerable 140.8.0esr-1~deb12u1 -
trixie (security), trixie vulnerable 140.8.0esr-1~deb13u1 -
forky, sid vulnerable 140.8.0esr-1 -
(unstable) fixed (unfixed) -

SUSE

Severity: Critical
Product Status
Image SLES15-SP5-SAP-Azure-LI-BYOS Image SLES15-SP5-SAP-Azure-LI-BYOS-Production Image SLES15-SP5-SAP-Azure-VLI-BYOS Image SLES15-SP5-SAP-Azure-VLI-BYOS-Production Image SLES15-SP6-SAP-Azure-LI-BYOS Image SLES15-SP6-SAP-Azure-LI-BYOS-Production Image SLES15-SP6-SAP-Azure-VLI-BYOS Image SLES15-SP6-SAP-Azure-VLI-BYOS-Production Image SLES15-SP7-SAP-Azure-LI-BYOS-Production Image SLES15-SP7-SAP-Azure-VLI-BYOS-Production Affected
SUSE Liberty Linux 10 Fixed
SUSE Liberty Linux 8 Fixed
SUSE Liberty Linux 9 Fixed
SUSE Linux Enterprise Desktop 15 SP7 SUSE Linux Enterprise Server 15 SP7 SUSE Linux Enterprise Server for SAP Applications 15 SP7 Fixed

Share

CVE-2026-4687 vulnerability details – vuln.today

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy