Mozilla Firefox up to 151 Workers sandbox

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-$25k1.73

Summaryinfo

A vulnerability was found in Mozilla Firefox up to 151 and classified as critical. This issue affects some unknown processing of the component Workers. The manipulation results in sandbox. This vulnerability was named CVE-2026-12294. The attack may be performed from remote. There is no available exploit. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Mozilla Firefox up to 151. Affected is an unknown code of the component Workers. The manipulation with an unknown input leads to a sandbox vulnerability. CWE is classifying the issue as CWE-265. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

Sandbox escape in the DOM: Workers component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, and Firefox ESR 115.37.

The advisory is available at bugzilla.mozilla.org. This vulnerability is traded as CVE-2026-12294 since 06/15/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Successful exploitation requires user interaction by the victim. 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 06/17/2026). This vulnerability is assigned to T1611 by the MITRE ATT&CK project.

The vulnerability scanner Nessus provides a plugin with the ID 321221 (Mozilla Thunderbird < 140.12), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 115.37, 140.12 or 152 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (321221). 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: 6.3
VulDB Meta Temp Score: 6.0

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

CVSSv2info

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

Exploitinginfo

Class: Sandbox
CWE: CWE-265 / CWE-264
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: 321221
Nessus Name: Mozilla Thunderbird < 140.12

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Firefox 115.37/140.12/152

Timelineinfo

06/15/2026 CVE reserved
06/16/2026 +1 days Advisory disclosed
06/16/2026 +0 days VulDB entry created
06/17/2026 +1 days VulDB entry last update

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CVE: CVE-2026-12294 (🔒)
GCVE (CVE): GCVE-0-2026-12294
GCVE (VulDB): GCVE-100-371298

Entryinfo

Created: 06/16/2026 16:19
Updated: 06/17/2026 11:11
Changes: 06/16/2026 16:19 (56), 06/17/2026 11:11 (2)
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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