Mozilla Firefox up to 153.1/154 Events clickjacking

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.1$5k-$25k0.00+

Summaryinfo

A vulnerability classified as problematic was found in Mozilla Firefox up to 153.1/154. Affected by this vulnerability is an unknown functionality of the component Events. Such manipulation leads to clickjacking. This vulnerability is listed as CVE-2026-84139. The attack may be performed from remote. There is no available exploit.

Detailsinfo

A vulnerability was found in Mozilla Firefox up to 153.1/154. It has been rated as problematic. Affected by this issue is an unknown function of the component Events. The manipulation with an unknown input leads to a clickjacking vulnerability. Using CWE to declare the problem leads to CWE-451. The user interface (UI) does not properly represent critical information to the user, allowing the information - or its source - to be obscured or spoofed. This is often a component in phishing attacks. Impacted is integrity. CVE summarizes:

Clickjacking issue in the DOM: Events component. This vulnerability was fixed in Firefox 155 and Firefox ESR 153.2.

The advisory is shared for download at bugzilla.mozilla.org. This vulnerability is handled as CVE-2026-84139 since 09/01/2026. 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. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 09/01/2026). The MITRE ATT&CK project declares the attack technique as T1566.003.

Upgrading to version 153.2 or 155 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

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Vendor

Name

Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.1

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

CVSSv2info

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

Exploitinginfo

Class: Clickjacking
CWE: CWE-451
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
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 153.2/155

Timelineinfo

09/01/2026 Advisory disclosed
09/01/2026 +0 days CVE reserved
09/01/2026 +0 days VulDB entry created
09/01/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CVE: CVE-2026-84139 (🔒)
GCVE (CVE): GCVE-0-2026-84139
GCVE (VulDB): GCVE-100-397628

Entryinfo

Created: 09/01/2026 15:15
Changes: 09/01/2026 15:15 (57)
Complete: 🔍
Cache ID: 216::103

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