Mozilla Firefox up to 146 Javascript GC use after free

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 categorized as critical has been discovered in Mozilla Firefox up to 146. This issue affects some unknown processing of the component Javascript GC. Such manipulation leads to use after free. This vulnerability is documented as CVE-2026-0885. The attack can be executed remotely. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in Mozilla Firefox up to 146. It has been rated as critical. Affected by this issue is an unknown functionality of the component Javascript GC. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability. CVE summarizes:

Use-after-free in the JavaScript: GC component. This vulnerability affects Firefox < 147, Firefox ESR < 140.7, Thunderbird < 147, and Thunderbird < 140.7.

The advisory is available at bugzilla.mozilla.org. This vulnerability is handled as CVE-2026-0885 since 01/13/2026. 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 06/11/2026).

The vulnerability scanner Nessus provides a plugin with the ID 284821 (RHEL 8 : firefox (RHSA-2026:0667)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 147 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (284821), EUVD (EUVD-2026-2077) and CERT Bund (WID-SEC-2026-0090). 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
  • 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: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-DayUnlockUnlockUnlockUnlock
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Nessus ID: 284821
Nessus Name: RHEL 8 : firefox (RHSA-2026:0667)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Firefox 147

Timelineinfo

01/13/2026 Advisory disclosed
01/13/2026 +0 days CVE reserved
01/13/2026 +0 days VulDB entry created
06/11/2026 +149 days VulDB entry last update

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CVE: CVE-2026-0885 (🔒)
GCVE (CVE): GCVE-0-2026-0885
GCVE (VulDB): GCVE-100-340586
EUVD: 🔒
CERT Bund: WID-SEC-2026-0090 - Mozilla Firefox und Thunderbird: Mehrere Schwachstellen

Entryinfo

Created: 01/13/2026 15:21
Updated: 06/11/2026 19:54
Changes: 01/13/2026 15:21 (56), 01/14/2026 22:33 (1), 01/15/2026 16:50 (2), 01/15/2026 17:13 (1), 01/15/2026 21:47 (7), 01/23/2026 01:41 (1), 06/11/2026 19:54 (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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