Mozilla Firefox up to 153.1/154 Push Subscriptions isolation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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8.4$5k-$25k0.00

Summaryinfo

A vulnerability labeled as critical has been found in Mozilla Firefox up to 153.1/154. This issue affects some unknown processing of the component Push Subscriptions. Such manipulation leads to isolation. This vulnerability is referenced as CVE-2026-84133. It is possible to launch the attack remotely. No exploit is available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Mozilla Firefox up to 153.1/154. It has been rated as critical. Affected by this issue is an unknown part of the component Push Subscriptions. The manipulation with an unknown input leads to a isolation vulnerability. Using CWE to declare the problem leads to CWE-653. The product does not properly compartmentalize or isolate functionality, processes, or resources that require different privilege levels, rights, or permissions. Impacted is confidentiality, integrity, and availability. CVE summarizes:

Site isolation issue in the DOM: Push Subscriptions component. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2.

The advisory is available at bugzilla.mozilla.org. This vulnerability is handled as CVE-2026-84133 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. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 09/08/2026).

The vulnerability scanner Nessus provides a plugin with the ID 342305 (Linux Distros Unpatched Vulnerability : CVE-2026-84133), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 153.2 or 155 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (342305) and CERT Bund (WID-SEC-2026-3132). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

  • Debian Linux
  • SUSE openSUSE
  • Mozilla Firefox
  • Mozilla Firefox ESR
  • Mozilla Thunderbird

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.5
VulDB Meta Temp Score: 8.4

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
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: Isolation
CWE: CWE-653
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: 342305
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-84133

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
09/08/2026 +7 days VulDB entry last update

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CVE: CVE-2026-84133 (🔒)
GCVE (CVE): GCVE-0-2026-84133
GCVE (VulDB): GCVE-100-397610
CERT Bund: WID-SEC-2026-3132 - Mozilla Firefox und Thunderbird: Mehrere Schwachstellen

Entryinfo

Created: 09/01/2026 15:00
Updated: 09/08/2026 08:03
Changes: 09/01/2026 15:00 (57), 09/03/2026 01:49 (2), 09/07/2026 05:28 (12), 09/08/2026 08:03 (7)
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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