Mozilla Firefox up to 140.12/152 JIT Remote Code Execution

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.0$5k-$25k2.32-

Summaryinfo

A vulnerability has been found in Mozilla Firefox up to 140.12/152 and classified as critical. The affected element is an unknown function of the component JIT. Performing a manipulation results in Remote Code Execution. This vulnerability is cataloged as CVE-2026-16363. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability was found in Mozilla Firefox up to 140.12/152. It has been classified as critical. This affects an unknown part of the component JIT. The manipulation with an unknown input leads to a remote code execution vulnerability. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

JIT miscompilation in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 153 and Firefox ESR 140.13.

It is possible to read the advisory at bugzilla.mozilla.org. This vulnerability is uniquely identified as CVE-2026-16363 since 07/20/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 07/21/2026).

Upgrading to version 140.13 or 153 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.0

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
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: Remote Code Execution
CWE: Unknown
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Upgrade: Firefox 140.13/153

Timelineinfo

07/20/2026 CVE reserved
07/21/2026 +1 days Advisory disclosed
07/21/2026 +0 days VulDB entry created
07/21/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CVE: CVE-2026-16363 (🔒)
GCVE (CVE): GCVE-0-2026-16363
GCVE (VulDB): GCVE-100-380859

Entryinfo

Created: 07/21/2026 15:08
Changes: 07/21/2026 15:08 (53)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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