capricorn86 Happy DOM up to 21.0.1 ServerRendererServer ServerRendererServer.ts onIncomingRequest :path path traversal

CVSS Meta Temp Score
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CTI Interest Score
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6.3$0-$5k0.00

Summaryinfo

A vulnerability was found in capricorn86 Happy DOM up to 21.0.1. It has been rated as problematic. This vulnerability affects the function onIncomingRequest of the file packages/@happy-dom/server-renderer/src/ServerRendererServer.ts of the component ServerRendererServer. Performing a manipulation of the argument :path results in path traversal. This vulnerability is identified as CVE-2026-118659. The attack can be initiated remotely. There is not any exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as problematic has been found in capricorn86 Happy DOM up to 21.0.1. This affects the function onIncomingRequest of the file packages/@happy-dom/server-renderer/src/ServerRendererServer.ts of the component ServerRendererServer. The manipulation of the argument :path with an unknown input leads to a path traversal vulnerability. CWE is classifying the issue as CWE-23. The product uses external input to construct a pathname that should be within a restricted directory, but it does not properly neutralize sequences such as ".." that can resolve to a location that is outside of that directory. This is going to have an impact on confidentiality. The summary by CVE is:

Happy DOM is a JavaScript implementation of a web browser without its graphical user interface. Prior to 21.0.2, the Happy DOM server-renderer package's ServerRendererServer accepts unauthenticated HTTP/2 requests and resolves attacker-controlled :path values against server.targetOrigin in #onIncomingRequest in packages/@happy-dom/server-renderer/src/ServerRendererServer.ts without confirming that the resolved origin remains trusted before calling fetch. A protocol-relative path can change the destination to an arbitrary HTTP or HTTPS endpoint reachable by the server, including local and internal services, and the proxy relays the fetched response headers and body to the requester. This issue is fixed in version 21.0.2.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2026-118659 since 10/28/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1006 according to MITRE ATT&CK.

Upgrading to version 21.0.2 eliminates this vulnerability.

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

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: Path traversal
CWE: CWE-23 / CWE-22
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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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Happy DOM 21.0.2

Timelineinfo

10/28/2026 Advisory disclosed
10/28/2026 +0 days CVE reserved
10/28/2026 +0 days VulDB entry created
10/28/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CNA: GitHub_M
CVE: CVE-2026-118659 (🔒)

GCVE (CVE): GCVE-0-2026-118659
GCVE (VulDB): GCVE-100-428211

Entryinfo

Created: 10/28/2026 21:37
Changes: 10/28/2026 21:37 (67)
Complete: 🔍
Cache ID: 216::103

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