Mozilla Firefox up to 148 Telemetry sandbox

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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8.1$5k-$25k0.00

Summaryinfo

A vulnerability was found in Mozilla Firefox up to 148 and classified as critical. This affects an unknown function of the component Telemetry. The manipulation results in sandbox. This vulnerability is cataloged as CVE-2026-4687. The attack may be launched remotely. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Mozilla Firefox up to 148. It has been classified as critical. Affected is an unknown code of the component Telemetry. The manipulation with an unknown input leads to a sandbox vulnerability. CWE is classifying the issue as CWE-265. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

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

The advisory is available at bugzilla.mozilla.org. This vulnerability is traded as CVE-2026-4687 since 03/24/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Successful exploitation requires user interaction by the victim. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 03/28/2026). This vulnerability is assigned to T1611 by the MITRE ATT&CK project.

The vulnerability scanner Nessus provides a plugin with the ID 303474 (Mozilla Firefox < 149.0), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 149 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (303474). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.2
VulDB Meta Temp Score: 8.1

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 8.6
NVD Vector: 🔒

ADP CISA Base Score: 9.6
ADP CISA Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Sandbox
CWE: CWE-265 / CWE-264
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 303474
Nessus Name: Mozilla Firefox < 149.0

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Firefox 149

Timelineinfo

03/24/2026 Advisory disclosed
03/24/2026 +0 days CVE reserved
03/24/2026 +0 days VulDB entry created
03/28/2026 +4 days VulDB entry last update

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CVE: CVE-2026-4687 (🔒)
GCVE (CVE): GCVE-0-2026-4687
GCVE (VulDB): GCVE-100-352734

Entryinfo

Created: 03/24/2026 14:16
Updated: 03/28/2026 17:15
Changes: 03/24/2026 14:16 (56), 03/25/2026 00:57 (2), 03/28/2026 17:15 (22)
Complete: 🔍
Cache ID: 216:614:103

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