Mozilla Firefox up to 140.11 Internationalization memory corruption

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-$25k0.00

Summaryinfo

A vulnerability marked as critical has been reported in Mozilla Firefox up to 140.11. The affected element is an unknown function of the component Internationalization. The manipulation leads to memory corruption. This vulnerability is listed as CVE-2026-12330. The attack may be initiated remotely. There is no available exploit. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Mozilla Firefox up to 140.11. This issue affects an unknown code of the component Internationalization. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Incorrect boundary conditions in the Internationalization component. This vulnerability was fixed in Firefox ESR 140.12 and Firefox ESR 115.37.

The advisory is shared at bugzilla.mozilla.org. The identification of this vulnerability is CVE-2026-12330 since 06/15/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. 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 07/10/2026).

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 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (321490) and CERT Bund (WID-SEC-2026-1959). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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

Exploitinginfo

Class: Memory corruption
CWE: CWE-119
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

Timelineinfo

06/15/2026 CVE reserved
06/16/2026 +1 days Advisory disclosed
06/16/2026 +0 days VulDB entry created
07/10/2026 +24 days VulDB entry last update

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CVE: CVE-2026-12330 (🔒)
GCVE (CVE): GCVE-0-2026-12330
GCVE (VulDB): GCVE-100-371333
CERT Bund: WID-SEC-2026-1959 - Mozilla Firefox, Firefox ESR und Thunderbird: Mehrere Schwachstellen

Entryinfo

Created: 06/16/2026 16:31
Updated: 07/10/2026 06:45
Changes: 06/16/2026 16:31 (56), 06/19/2026 05:17 (2), 06/20/2026 12:47 (7), 07/10/2026 06:45 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Discussion

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