Mozilla Firefox up to 148 Anti-Tracking authentication spoofing

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.7$0-$5k0.86

Summaryinfo

A vulnerability was found in Mozilla Firefox up to 148. It has been declared as problematic. This affects an unknown function of the component Anti-Tracking. Such manipulation leads to an unknown weakness. This vulnerability is listed as CVE-2026-4728. The attack may be performed from remote. There is no available exploit. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Mozilla Firefox up to 148 and classified as problematic. Affected by this issue is some unknown processing of the component Anti-Tracking. Using CWE to declare the problem leads to CWE-290. This attack-focused weakness is caused by incorrectly implemented authentication schemes that are subject to spoofing attacks. Impacted is integrity. CVE summarizes:

Spoofing issue in the Privacy: Anti-Tracking component. This vulnerability affects Firefox < 149 and Thunderbird < 149.

The advisory is available at bugzilla.mozilla.org. This vulnerability is handled as CVE-2026-4728 since 03/24/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. 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 $0-$5k at the moment (estimation calculated on 03/28/2026).

The vulnerability scanner Nessus provides a plugin with the ID 304115 (Linux Distros Unpatched Vulnerability : CVE-2026-4728), 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 (304115). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.8
VulDB Meta Temp Score: 5.7

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔒

ADP CISA Base Score: 6.5
ADP CISA Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Authentication spoofing
CWE: CWE-290 / CWE-287
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: 304115
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-4728

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-2026-4728 (🔒)
GCVE (CVE): GCVE-0-2026-4728
GCVE (VulDB): GCVE-100-352778

Entryinfo

Created: 03/24/2026 14:47
Updated: 03/28/2026 20:34
Changes: 03/24/2026 14:47 (54), 03/28/2026 10:23 (2), 03/28/2026 20:34 (24)
Complete: 🔍
Cache ID: 216:8B2:103

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