CVE-2025-27109: Solid js Cross-Site Scripting Vulnerability

HIGH
Advisory Identifier: GHSA-3qxh-p7jc-5xh6
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CVSS 7.3
CWE-116 CWE-79
Published
Advisory Summary

CVE-2025-27109 is a HIGH (CVSS 7.3) cross-site scripting vulnerability (CWE-116: Improper Encoding or Escaping of Output) affecting Solid js libraries in the npm ecosystem. The issue involves solid lacks escaping of html in jsx fragments allows for cross-site scripting (xss). Remediation is available by upgrading affected packages to version 1.9.4.

CVE-2025-27109 at a Glance

CVE Identifier CVE-2025-27109
GHSA Identifier GHSA-3qxh-p7jc-5xh6
Severity HIGH
CVSS v3.1 Base Score 7.3
CWE Classification CWE-116: Improper Encoding or Escaping of Output
Affected Product Solid js
Package Ecosystem npm
Published Date
Last Updated

Security Impact

CVSS: 7.3

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality Low (C:L)
Integrity Low (I:L)
Availability Low (A:L)

How to Fix CVE-2025-27109

To remediate this vulnerability, upgrade all affected Solid js dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

solid-js fixed: 1.9.4 
npm install solid-js@1.9.4
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

npm ls solid-js

How to Check if You Are Affected

To determine whether your Node.js application is affected by CVE-2025-27109, inspect your project dependencies using npm:

npm ls solid-js

Analyze the terminal output to locate any version of Solid js in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.9.4), your application is affected.

Note: The npm ls solid-js command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-116: Improper Encoding or Escaping of Output, where the product prepares a structured message for communication with another component, but encoding or escaping of the data is either missing or done incorrectly. as a result, the intended structure of the message is not preserved. In Solid js, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

Inserts/JSX expressions inside illegal inlined JSX fragments lacked escaping, allowing user input to be rendered as HTML when put directly inside JSX fragments. For instance, `?text=<svg/onload=alert(1)>` would trigger XSS here. ```js const [text] = createResource(() => { return new URL(getRequestEvent().request.url).searchParams.get("text"); }); return ( <> Text: {text()} </> ); ```

CVE-2025-27109 Affected Solid js Versions

1 component(s)
Fixed Versions:
1.9.4
Product / Package Ecosystem Affected Versions Fixed Version
solid-js
npm/solid-js
npm
< 1.9.4
1.9.4

References

GitHub Advisory / Wiki ADVISORY
https://github.com/solidjs/solid/security/advisories/GHSA-3qxh-p7jc-5xh6
NVD — CVE-2025-27109 NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-27109
Security Fix Commit FIX COMMIT
https://github.com/solidjs/solid/commit/b93956f28ed75469af6976a98728e313d0edd236
Solid js Source Repository REPOSITORY
https://github.com/solidjs/solid

Frequently Asked Questions

What is CVE-2025-27109?
CVE-2025-27109 is a security vulnerability in Solid js involving Solid Lacks Escaping of HTML in JSX Fragments allows for Cross-Site Scripting (XSS) under CWE-116: Improper Encoding or Escaping of Output.
Which Solid js versions are affected?
Affected versions include releases prior to 1.9.4 across affected packages: solid-js.
What version fixes CVE-2025-27109?
Upgrading to 1.9.4 (or the latest patched release for your respective branch) resolves the vulnerability.
Is solid-js affected?
Yes, solid-js is affected in releases prior to 1.9.4. Upgrade your dependency to 1.9.4 or later.
What is the CVSS score of CVE-2025-27109?
CVE-2025-27109 has a CVSS v3.1 base score of 7.3 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L.
What CWE is associated with CVE-2025-27109?
CVE-2025-27109 is classified under CWE-116: Improper Encoding or Escaping of Output (The product prepares a structured message for communication with another component, but encoding or escaping of the data is either missing or done incorrectly. As a result, the intended structure of the message is not preserved.).
How can I check npm dependencies for CVE-2025-27109?
Run the dependency tree command: 'npm ls solid-js'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-3qxh-p7jc-5xh6",
  "modified" : "2025-02-25T17:49:40Z",
  "published" : "2025-02-25T17:49:40Z",
  "aliases" : [ "CVE-2025-27109" ],
  "summary" : "Solid Lacks Escaping of HTML in JSX Fragments allows for Cross-Site Scripting (XSS)",
  "details" : "Inserts/JSX expressions inside illegal inlined JSX fragments lacked escaping, allowing user input to be rendered as HTML when put directly inside JSX fragments.\n\nFor instance, `?text=<svg/onload=alert(1)>` would trigger XSS here.\n```js\n  const [text] = createResource(() => {\n    return new URL(getRequestEvent().request.url).searchParams.get(\"text\");\n  });\n\n  return (\n    <>\n      Text: {text()}\n    </>\n  );\n  ```",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "solid-js"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.9.4"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/solidjs/solid/security/advisories/GHSA-3qxh-p7jc-5xh6"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-27109"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/solidjs/solid/commit/b93956f28ed75469af6976a98728e313d0edd236"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/solidjs/solid"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-116", "CWE-79" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2025-02-25T17:49:40Z",
    "nvd_published_at" : "2025-02-21T22:15:14Z"
  }
}