Mozilla Firefox up to 152 Navigation improper isolation or compartmentalization

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.0$5k-$25k1.07

Summaryinfo

A vulnerability was found in Mozilla Firefox up to 152. It has been rated as critical. This affects an unknown function of the component Navigation. This manipulation causes improper isolation or compartmentalization. This vulnerability is registered as CVE-2026-16399. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability was found in Mozilla Firefox up to 152. It has been declared as critical. Affected by this vulnerability is an unknown function of the component Navigation. The manipulation with an unknown input leads to a improper isolation or compartmentalization vulnerability. The CWE definition for the vulnerability is CWE-653. The product does not properly compartmentalize or isolate functionality, processes, or resources that require different privilege levels, rights, or permissions. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

Site isolation issue in the DOM: Navigation component. This vulnerability was fixed in Firefox 153.

The advisory is shared at bugzilla.mozilla.org. This vulnerability is known as CVE-2026-16399 since 07/20/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. 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 07/21/2026).

Upgrading to version 153 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
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: Improper isolation or compartmentalization
CWE: CWE-653
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: no mitigation known
Status: 🔍

0-Day Time: 🔒

Upgrade: Firefox 153

Timelineinfo

07/20/2026 CVE reserved
07/21/2026 +1 days Advisory disclosed
07/21/2026 +0 days VulDB entry created
07/21/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CVE: CVE-2026-16399 (🔒)
GCVE (CVE): GCVE-0-2026-16399
GCVE (VulDB): GCVE-100-380905

Entryinfo

Created: 07/21/2026 16:16
Changes: 07/21/2026 16:16 (54)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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