Mozilla Firefox up to 115.43/153.5/158 JavaScript Engine integer overflow

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-$25k0.32+

Summaryinfo

A vulnerability identified as critical has been detected in Mozilla Firefox up to 115.43/153.5/158. Affected by this vulnerability is an unknown functionality of the component JavaScript Engine. Performing a manipulation results in integer overflow. This vulnerability is reported as CVE-2026-117946. The attack is possible to be carried out remotely. No exploit exists. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Mozilla Firefox up to 115.43/153.5/158. It has been classified as critical. This affects some unknown functionality of the component JavaScript Engine. The manipulation with an unknown input leads to a integer overflow vulnerability. CWE is classifying the issue as CWE-190. The product performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Incorrect boundary conditions in the JavaScript Engine component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, and Firefox ESR 153.6.

The advisory is shared at bugzilla.mozilla.org. This vulnerability is uniquely identified as CVE-2026-117946 since 10/27/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for 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 10/27/2026).

Upgrading to version 115.44, 153.6 or 159 eliminates this vulnerability.

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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: Integer overflow
CWE: CWE-190 / CWE-189
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: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Firefox 115.44/153.6/159

Timelineinfo

10/27/2026 Advisory disclosed
10/27/2026 +0 days CVE reserved
10/27/2026 +0 days VulDB entry created
10/27/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CVE: CVE-2026-117946 (🔒)
GCVE (CVE): GCVE-0-2026-117946
GCVE (VulDB): GCVE-100-427317

Entryinfo

Created: 10/27/2026 15:54
Changes: 10/27/2026 15:54 (57)
Complete: 🔍
Cache ID: 216::103

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