Mozilla Firefox up to 140 on iOS iFrame access control

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.9$5k-$25k0.00

Summaryinfo

A vulnerability classified as critical has been found in Mozilla Firefox up to 140 on iOS. This affects an unknown function of the component iFrame Handler. The manipulation leads to access control. This vulnerability is traded as CVE-2025-54143. It is possible to initiate the attack remotely. There is no exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Mozilla Firefox up to 140 on iOS. It has been rated as critical. This issue affects some unknown processing of the component iFrame Handler. The manipulation with an unknown input leads to a access control vulnerability. Using CWE to declare the problem leads to CWE-284. The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Sandboxed iframes on webpages could potentially allow downloads to the device, bypassing the expected sandbox restrictions declared on the parent page. This vulnerability was fixed in Firefox for iOS 141.

The advisory is shared at bugzilla.mozilla.org. The identification of this vulnerability is CVE-2025-54143 since 07/17/2025. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 10/06/2026). MITRE ATT&CK project uses the attack technique T1068 for this issue.

Upgrading to version 141 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2025-25230). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.0
VulDB Meta Temp Score: 7.9

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

ADP CISA Base Score: 9.8
ADP CISA Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Access control
CWE: CWE-284 / CWE-266
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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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Firefox 141

Timelineinfo

07/17/2025 🔍
08/19/2025 +33 days 🔍
08/19/2025 +0 days 🔍
10/06/2026 +413 days 🔍

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CVE: CVE-2025-54143 (🔍)
GCVE (CVE): GCVE-0-2025-54143
GCVE (VulDB): GCVE-100-320669
EUVD: 🔍

Entryinfo

Created: 08/19/2025 23:29
Updated: 10/06/2026 06:11
Changes: 08/19/2025 23:29 (57), 08/20/2025 05:43 (1), 08/20/2025 10:37 (1), 10/01/2026 21:10 (15), 10/06/2026 06:11 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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