Mozilla Firefox up to 135 on Android Custom Tabs permission

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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3.5$0-$5k0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in Mozilla Firefox up to 135 on Android. Affected by this issue is some unknown functionality of the component Custom Tabs. The manipulation results in permission. This vulnerability is known as CVE-2025-1939. Attacking locally is a requirement. No exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in Mozilla Firefox up to 135 on Android. Affected is an unknown functionality of the component Custom Tabs. The manipulation with an unknown input leads to a permission vulnerability. CWE is classifying the issue as CWE-275. This is going to have an impact on confidentiality. CVE summarizes:

Android apps can load web pages using the Custom Tabs feature. This feature supports a transition animation that could have been used to trick a user into granting sensitive permissions by hiding what the user was actually clicking. This vulnerability was fixed in Firefox 136.

The advisory is available at bugzilla.mozilla.org. This vulnerability is traded as CVE-2025-1939 since 03/04/2025. The exploitability is told to be easy. Local access is required to approach this attack. 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 04/15/2026). This vulnerability is assigned to T1222 by the MITRE ATT&CK project.

Upgrading to version 136 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 3.6
VulDB Meta Temp Score: 3.5

VulDB Base Score: 3.3
VulDB Temp Score: 3.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

ADP CISA Base Score: 3.9
ADP CISA Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Permission
CWE: CWE-275 / CWE-266
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Firefox 136

Timelineinfo

03/04/2025 🔍
03/04/2025 +0 days 🔍
03/04/2025 +0 days 🔍
04/15/2026 +407 days 🔍

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CVE: CVE-2025-1939 (🔍)
GCVE (CVE): GCVE-0-2025-1939
GCVE (VulDB): GCVE-100-298530
scip Labs: https://www.scip.ch/en/?labs.20130704

Entryinfo

Created: 03/04/2025 15:08
Updated: 04/15/2026 12:11
Changes: 03/04/2025 15:08 (57), 09/08/2025 04:47 (1), 04/15/2026 12:11 (12)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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