CVE-2023-31125: Engine.io Engine.io Uncaught Exception Vulnerability Vulnerability

MODERATE
Advisory Identifier: GHSA-q9mw-68c2-j6m5
CVSS 6.5
CWE-248
Published
Advisory Summary

CVE-2023-31125 is a MODERATE (CVSS 6.5) engine.io uncaught exception vulnerability vulnerability (CWE-248: Uncaught Exception) affecting Engine.io libraries in the npm ecosystem. The issue involves engine.io uncaught exception vulnerability. Remediation is available by upgrading affected packages to version 6.4.2.

CVE-2023-31125 at a Glance

CVE Identifier CVE-2023-31125
GHSA Identifier GHSA-q9mw-68c2-j6m5
Severity MODERATE
CVSS v3.1 Base Score 6.5
CWE Classification CWE-248: Uncaught Exception
Affected Product Engine.io
Package Ecosystem npm
Published Date
Last Updated

Security Impact

CVSS: 6.5

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

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

How to Fix CVE-2023-31125

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

engine.io fixed: 6.4.2
npm install engine.io@6.4.2
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 engine.io

How to Check if You Are Affected

To determine whether your Node.js application is affected by CVE-2023-31125, inspect your project dependencies using npm:

npm ls engine.io

Analyze the terminal output to locate any version of Engine.io in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 6.4.2), your application is affected.

Note: The npm ls engine.io 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-248: Uncaught Exception, where an exception is thrown from a function, but it is not caught. In Engine.io, 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

### Impact A specially crafted HTTP request can trigger an uncaught exception on the Engine.IO server, thus killing the Node.js process. ``` TypeError: Cannot read properties of undefined (reading 'handlesUpgrades') at Server.onWebSocket (build/server.js:515:67) ``` This impacts all the users of the [`engine.io`](https://www.npmjs.com/package/engine.io) package, including those who uses depending packages like [`socket.io`](https://www.npmjs.com/package/socket.io). ### Patches A fix has been released today (2023/05/02): [6.4.2](https://github.com/socketio/engine.io/releases/tag/6.4.2) This bug was introduced in version 5.1.0 and included in version 4.1.0 of the `socket.io` parent package. Older versions are not impacted. For `socket.io` users: | Version range | `engine.io` version | Needs minor update? | |-----------------------------|---------------------|--------------------------------------------------------------------------------------------------------| | `socket.io@4.6.x` | `~6.4.0` | `npm audit fix` should be sufficient | | `socket.io@4.5.x` | `~6.2.0` | Please upgrade to `socket.io@4.6.x` | | `socket.io@4.4.x` | `~6.1.0` | Please upgrade to `socket.io@4.6.x` | | `socket.io@4.3.x` | `~6.0.0` | Please upgrade to `socket.io@4.6.x` | | `socket.io@4.2.x` | `~5.2.0` | Please upgrade to `socket.io@4.6.x` | | `socket.io@4.1.x` | `~5.1.1` | Please upgrade to `socket.io@4.6.x` | | `socket.io@4.0.x` | `~5.0.0` | Not impacted | | `socket.io@3.1.x` | `~4.1.0` | Not impacted | | `socket.io@3.0.x` | `~4.0.0` | Not impacted | | `socket.io@2.5.0` | `~3.6.0` | Not impacted | | `socket.io@2.4.x` and below | `~3.5.0` | Not impacted | ### Workarounds There is no known workaround except upgrading to a safe version. ### For more information If you have any questions or comments about this advisory: * Open an issue in [`engine.io`](https://github.com/socketio/engine.io) Thanks to Thomas Rinsma from Codean for the responsible disclosure.

CVE-2023-31125 Affected Engine.io Versions

1 component(s)
Fixed Versions:
6.4.2
Product / Package Ecosystem Affected Versions Fixed Version
engine.io
npm
≥ 5.1.0
< 6.4.2
6.4.2

References

Frequently Asked Questions

What is CVE-2023-31125?
CVE-2023-31125 is a security vulnerability in Engine.io involving engine.io Uncaught Exception vulnerability under CWE-248: Uncaught Exception.
Which Engine.io versions are affected?
Affected versions include releases prior to 6.4.2 across affected packages: engine.io.
What version fixes CVE-2023-31125?
Upgrading to 6.4.2 (or the latest patched release for your respective branch) resolves the vulnerability.
Is engine.io affected?
Yes, engine.io is affected in releases prior to 6.4.2. Upgrade your dependency to 6.4.2 or later.
What is the CVSS score of CVE-2023-31125?
CVE-2023-31125 has a CVSS v3.1 base score of 6.5 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
What CWE is associated with CVE-2023-31125?
CVE-2023-31125 is classified under CWE-248: Uncaught Exception (An exception is thrown from a function, but it is not caught.).
How can I check npm dependencies for CVE-2023-31125?
Run the dependency tree command: 'npm ls engine.io'. 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
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-q9mw-68c2-j6m5",
  "modified" : "2025-02-13T18:54:10Z",
  "published" : "2023-05-03T21:56:51Z",
  "aliases" : [ "CVE-2023-31125" ],
  "summary" : "engine.io Uncaught Exception vulnerability",
  "details" : "### Impact\n\nA specially crafted HTTP request can trigger an uncaught exception on the Engine.IO server, thus killing the Node.js process.\n\n```\nTypeError: Cannot read properties of undefined (reading 'handlesUpgrades')\n    at Server.onWebSocket (build/server.js:515:67)\n```\n\nThis impacts all the users of the [`engine.io`](https://www.npmjs.com/package/engine.io) package, including those who uses depending packages like [`socket.io`](https://www.npmjs.com/package/socket.io).\n\n### Patches\n\nA fix has been released today (2023/05/02): [6.4.2](https://github.com/socketio/engine.io/releases/tag/6.4.2)\n\nThis bug was introduced in version 5.1.0 and included in version 4.1.0 of the `socket.io` parent package. Older versions are not impacted.\n\nFor `socket.io` users:\n\n| Version range               | `engine.io` version | Needs minor update?                                                                                    |\n|-----------------------------|---------------------|--------------------------------------------------------------------------------------------------------|\n| `socket.io@4.6.x`           | `~6.4.0`            | `npm audit fix` should be sufficient                                                                   |\n| `socket.io@4.5.x`           | `~6.2.0`            | Please upgrade to `socket.io@4.6.x`                                                                    |\n| `socket.io@4.4.x`           | `~6.1.0`            | Please upgrade to `socket.io@4.6.x`                                                                    |\n| `socket.io@4.3.x`           | `~6.0.0`            | Please upgrade to `socket.io@4.6.x`                                                                    |\n| `socket.io@4.2.x`           | `~5.2.0`            | Please upgrade to `socket.io@4.6.x`                                                                    |\n| `socket.io@4.1.x`           | `~5.1.1`            | Please upgrade to `socket.io@4.6.x`                                                                    |\n| `socket.io@4.0.x`           | `~5.0.0`            | Not impacted |\n| `socket.io@3.1.x`           | `~4.1.0`            | Not impacted |\n| `socket.io@3.0.x`           | `~4.0.0`            | Not impacted |\n| `socket.io@2.5.0`           | `~3.6.0`            | Not impacted |\n| `socket.io@2.4.x` and below | `~3.5.0`            | Not impacted |\n\n### Workarounds\n\nThere is no known workaround except upgrading to a safe version.\n\n### For more information\n\nIf you have any questions or comments about this advisory:\n\n* Open an issue in [`engine.io`](https://github.com/socketio/engine.io)\n\nThanks to Thomas Rinsma from Codean for the responsible disclosure.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "engine.io"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "5.1.0"
      }, {
        "fixed" : "6.4.2"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/socketio/engine.io/security/advisories/GHSA-q9mw-68c2-j6m5"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2023-31125"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/socketio/engine.io/commit/fc480b4f305e16fe5972cf337d055e598372dc44"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/socketio/engine.io"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/socketio/engine.io/releases/tag/6.4.2"
  }, {
    "type" : "WEB",
    "url" : "https://security.netapp.com/advisory/ntap-20230622-0002"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-248" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2023-05-03T21:56:51Z",
    "nvd_published_at" : "2023-05-08T21:15:11Z"
  }
}