Mozilla Firefox up to 140.11/151 Process Sandboxing sandbox

CVSS Meta Temp Score
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CTI Interest Score
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6.0$5k-$25k0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in Mozilla Firefox up to 140.11/151. Affected by this vulnerability is an unknown functionality of the component Process Sandboxing. The manipulation results in sandbox. This vulnerability is identified as CVE-2026-12311. The attack can be executed remotely. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Mozilla Firefox up to 140.11/151. Affected is an unknown functionality of the component Process Sandboxing. 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:

Information disclosure, sandbox escape in the Security: Process Sandboxing component. This vulnerability was fixed in Firefox 152 and Firefox ESR 140.12.

The advisory is shared for download at bugzilla.mozilla.org. This vulnerability is traded as CVE-2026-12311 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. 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 07/09/2026). The MITRE ATT&CK project declares the attack technique as T1611.

The vulnerability scanner Nessus provides a plugin with the ID 321490 (Debian dsa-6350 : firefox-esr - security update), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 140.12 or 152 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (321490) and CERT Bund (WID-SEC-2026-1959). Once again VulDB remains the best source for vulnerability data.

Affected

  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • IGEL OS
  • SUSE openSUSE
  • RESF Rocky Linux
  • 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: 6.3
VulDB Meta Temp Score: 6.0

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

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
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: 321490
Nessus Name: Debian dsa-6350 : firefox-esr - security update

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Firefox 140.12/152

Timelineinfo

06/15/2026 CVE reserved
06/16/2026 +1 days Advisory disclosed
06/16/2026 +0 days VulDB entry created
07/09/2026 +23 days VulDB entry last update

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CVE: CVE-2026-12311 (🔒)
GCVE (CVE): GCVE-0-2026-12311
GCVE (VulDB): GCVE-100-371316
CERT Bund: WID-SEC-2026-1959 - Mozilla Firefox, Firefox ESR und Thunderbird: Mehrere Schwachstellen

Entryinfo

Created: 06/16/2026 16:25
Updated: 07/09/2026 23:13
Changes: 06/16/2026 16:25 (56), 06/19/2026 00:01 (2), 06/20/2026 10:28 (7), 07/09/2026 23:13 (1)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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