SvelteJS SvelteKit up to 3.1.0 Build-time server-only module guard src/params.js information disclosure

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.3$0-$5k0.23+

Summaryinfo

A vulnerability classified as problematic was found in SvelteJS SvelteKit up to 3.1.0. The impacted element is an unknown function of the file src/params.js of the component Build-time server-only module guard. Executing a manipulation can lead to information disclosure. This vulnerability is registered as CVE-2026-128118. It is possible to launch the attack remotely. No exploit is available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in SvelteJS SvelteKit up to 3.1.0. It has been declared as problematic. This vulnerability affects an unknown function of the file src/params.js of the component Build-time server-only module guard. The manipulation with an unknown input leads to a information disclosure vulnerability. The CWE definition for the vulnerability is CWE-200. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. As an impact it is known to affect confidentiality. CVE summarizes:

SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. From version 3.0.0 until 3.1.1, the build-time server-only module guard did not treat src/params.js as a client entry point even though parameter matchers can run in the browser. Server-only modules imported through src/params.js could consequently enter the client bundle, where statically replaced private environment values or other server secrets could be exposed. This issue is fixed in 3.1.1.

The advisory is available at github.com. This vulnerability was named CVE-2026-128118 since 11/12/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1592 by the MITRE ATT&CK project.

Upgrading to version 3.1.1 eliminates this vulnerability.

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

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.5
CNA Vector (GitHub_M): 🔒

CVSSv2info

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

Exploitinginfo

Class: Information disclosure
CWE: CWE-200 / CWE-284 / CWE-266
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: SvelteKit 3.1.1

Timelineinfo

11/12/2026 CVE reserved
11/13/2026 +1 days Advisory disclosed
11/13/2026 +0 days VulDB entry created
11/13/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CNA: GitHub_M
CVE: CVE-2026-128118 (🔒)

GCVE (CVE): GCVE-0-2026-128118
GCVE (VulDB): GCVE-100-437290

Entryinfo

Created: 11/13/2026 20:47
Changes: 11/13/2026 20:47 (65)
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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