Mozilla Firefox up to 151 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 described as critical has been identified in Mozilla Firefox up to 151. Affected by this issue is some unknown functionality. Such manipulation leads to memory corruption. This vulnerability is documented as CVE-2026-12305. The attack can be executed remotely. There is not any exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Mozilla Firefox up to 151. Affected by this issue is an unknown code block. 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. CVE summarizes:

Memory safety bug fixed in Firefox 152. This vulnerability was fixed in Firefox 152 and Firefox ESR 140.12.

The advisory is available at bugzilla.mozilla.org. This vulnerability is handled as CVE-2026-12305 since 06/15/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. 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 07/09/2026).

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 152 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 best quality of vulnerability data, you may have to visit 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
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
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 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-2026-12305 (🔒)
GCVE (CVE): GCVE-0-2026-12305
GCVE (VulDB): GCVE-100-371306
CERT Bund: WID-SEC-2026-1959 - Mozilla Firefox, Firefox ESR und Thunderbird: Mehrere Schwachstellen

Entryinfo

Created: 06/16/2026 16:21
Updated: 07/09/2026 19:16
Changes: 06/16/2026 16:21 (55), 06/18/2026 22:29 (2), 06/20/2026 10:11 (7), 07/09/2026 19:16 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Discussion

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