Mozilla Firefox up to 148 JIT type confusion

CVSS Meta Temp Score
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CTI Interest Score
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7.9$5k-$25k0.19

Summaryinfo

A vulnerability classified as problematic was found in Mozilla Firefox up to 148. This issue affects some unknown processing of the component JIT. Such manipulation leads to an unknown weakness. This vulnerability is referenced as CVE-2026-4698. It is possible to launch the attack remotely. No exploit is available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Mozilla Firefox up to 148. Affected by this issue is an unknown function of the component JIT. Using CWE to declare the problem leads to CWE-843. The product allocates or initializes a resource such as a pointer, object, or variable using one type, but it later accesses that resource using a type that is incompatible with the original type. Impacted is integrity. CVE summarizes:

JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, Firefox ESR < 140.9, Thunderbird < 149, and Thunderbird < 140.9.

The advisory is available at bugzilla.mozilla.org. This vulnerability is handled as CVE-2026-4698 since 03/24/2026. 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 04/14/2026).

The vulnerability scanner Nessus provides a plugin with the ID 303809 (RHEL 9 : firefox (RHSA-2026:5930)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 149 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (303809) and CERT Bund (WID-SEC-2026-0850). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

  • Debian Linux
  • Red Hat Enterprise 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: 8.0
VulDB Meta Temp Score: 7.9

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 9.8
NVD Vector: 🔒

ADP CISA Base Score: 9.8
ADP CISA Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Type confusion
CWE: CWE-843
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: 303809
Nessus Name: RHEL 9 : firefox (RHSA-2026:5930)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Firefox 149

Timelineinfo

03/24/2026 Advisory disclosed
03/24/2026 +0 days CVE reserved
03/24/2026 +0 days VulDB entry created
04/14/2026 +21 days VulDB entry last update

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CVE: CVE-2026-4698 (🔒)
GCVE (CVE): GCVE-0-2026-4698
GCVE (VulDB): GCVE-100-352730
CERT Bund: WID-SEC-2026-0850 - Mozilla Firefox und Mozilla Thunderbird: Mehrere Schwachstellen

Entryinfo

Created: 03/24/2026 14:14
Updated: 04/14/2026 10:24
Changes: 03/24/2026 14:14 (54), 03/26/2026 23:51 (2), 03/28/2026 18:15 (24), 04/14/2026 10:24 (7)
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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