CVE-2021-39157: Detect character encoding Improper Handling Of Exceptional Conditions Vulnerability

HIGH
Advisory Identifier: GHSA-jqfh-8hw5-fqjr
CVSS 7.5
CWE-755
Published
Advisory Summary

CVE-2021-39157 is a HIGH (CVSS 7.5) improper handling of exceptional conditions vulnerability (CWE-755: Improper Handling of Exceptional Conditions) affecting Detect character encoding libraries in the npm ecosystem. The issue involves improper handling of exceptional conditions in detect-character-encoding. Remediation is available by upgrading affected packages to version 0.7.0.

CVE-2021-39157 at a Glance

CVE Identifier CVE-2021-39157
GHSA Identifier GHSA-jqfh-8hw5-fqjr
Severity HIGH
CVSS v3.1 Base Score 7.5
CWE Classification CWE-755: Improper Handling of Exceptional Conditions
Affected Product Detect character encoding
Package Ecosystem npm
Published Date
Last Updated

Security Impact

CVSS: 7.5

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:N/I:N/A:H).

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 None (C:N)
Integrity None (I:N)
Availability High (A:H)

How to Fix CVE-2021-39157

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

detect-character-encoding fixed: 0.7.0
npm install detect-character-encoding@0.7.0
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 detect-character-encoding

How to Check if You Are Affected

To determine whether your Node.js application is affected by CVE-2021-39157, inspect your project dependencies using npm:

npm ls detect-character-encoding

Analyze the terminal output to locate any version of Detect character encoding in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.7.0), your application is affected.

Note: The npm ls detect-character-encoding 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-755: Improper Handling of Exceptional Conditions, where the product does not handle or incorrectly handles an exceptional condition. In Detect character encoding, 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 In detect-character-encoding v0.6.0 and earlier, data matching no charset causes the Node.js process to crash. ### Patches The problem has been patched in [detect-character-encoding v0.7.0](https://github.com/sonicdoe/detect-character-encoding/releases/tag/v0.7.0). ### CVSS score [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/RL:O/RC:C](https://www.first.org/cvss/calculator/3.1#CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/RL:O/RC:C) Base Score: 7.5 (High) Temporal Score: 7.2 (High) Since detect-character-encoding is a library, the scoring is based on the “[reasonable worst-case implementation scenario](https://www.first.org/cvss/v3.1/user-guide#3-7-Scoring-Vulnerabilities-in-Software-Libraries-and-Similar)”, namely, accepting data from untrusted sources over a network and passing it directly to detect-character-encoding. Depending on your specific implementation, the vulnerability’s severity in your program may be different. ### Proof of concept ```js const express = require("express"); const bodyParser = require("body-parser"); const detectCharacterEncoding = require("detect-character-encoding"); const app = express(); app.use(bodyParser.raw()); app.post("/", (req, res) => { const charsetMatch = detectCharacterEncoding(req.body); res.end(charsetMatch.encoding); }); app.listen(3000); ``` `printf "\xAA" | curl --request POST --header "Content-Type: application/octet-stream" --data-binary @- http://localhost:3000` crashes the server.

CVE-2021-39157 Affected Detect character encoding Versions

1 component(s)
Fixed Versions:
0.7.0
Product / Package Ecosystem Affected Versions Fixed Version
detect-character-encoding
npm
< 0.7.0
0.7.0

References

Frequently Asked Questions

What is CVE-2021-39157?
CVE-2021-39157 is a security vulnerability in Detect character encoding involving Improper Handling of Exceptional Conditions in detect-character-encoding under CWE-755: Improper Handling of Exceptional Conditions.
Which Detect character encoding versions are affected?
Affected versions include releases prior to 0.7.0 across affected packages: detect-character-encoding.
What version fixes CVE-2021-39157?
Upgrading to 0.7.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is detect-character-encoding affected?
Yes, detect-character-encoding is affected in releases prior to 0.7.0. Upgrade your dependency to 0.7.0 or later.
What is the CVSS score of CVE-2021-39157?
CVE-2021-39157 has a CVSS v3.1 base score of 7.5 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
What CWE is associated with CVE-2021-39157?
CVE-2021-39157 is classified under CWE-755: Improper Handling of Exceptional Conditions (The product does not handle or incorrectly handles an exceptional condition.).
How can I check npm dependencies for CVE-2021-39157?
Run the dependency tree command: 'npm ls detect-character-encoding'. 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-jqfh-8hw5-fqjr",
  "modified" : "2021-10-21T14:15:03Z",
  "published" : "2021-08-25T14:44:48Z",
  "aliases" : [ "CVE-2021-39157" ],
  "summary" : "Improper Handling of Exceptional Conditions in detect-character-encoding",
  "details" : "### Impact\n\nIn detect-character-encoding v0.6.0 and earlier, data matching no charset causes the Node.js process to crash.\n\n### Patches\n\nThe problem has been patched in [detect-character-encoding v0.7.0](https://github.com/sonicdoe/detect-character-encoding/releases/tag/v0.7.0).\n\n### CVSS score\n\n[CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/RL:O/RC:C](https://www.first.org/cvss/calculator/3.1#CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/RL:O/RC:C)\n\nBase Score: 7.5 (High)\nTemporal Score: 7.2 (High)\n\nSince detect-character-encoding is a library, the scoring is based on the “[reasonable worst-case implementation scenario](https://www.first.org/cvss/v3.1/user-guide#3-7-Scoring-Vulnerabilities-in-Software-Libraries-and-Similar)”, namely, accepting data from untrusted sources over a network and passing it directly to detect-character-encoding. Depending on your specific implementation, the vulnerability’s severity in your program may be different.\n\n### Proof of concept\n\n```js\nconst express = require(\"express\");\nconst bodyParser = require(\"body-parser\");\nconst detectCharacterEncoding = require(\"detect-character-encoding\");\n\nconst app = express();\n\napp.use(bodyParser.raw());\n\napp.post(\"/\", (req, res) => {\n  const charsetMatch = detectCharacterEncoding(req.body);\n\n  res.end(charsetMatch.encoding);\n});\n\napp.listen(3000);\n```\n\n`printf \"\\xAA\" | curl --request POST --header \"Content-Type: application/octet-stream\" --data-binary @- http://localhost:3000` crashes the server.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "detect-character-encoding"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "0.7.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/sonicdoe/detect-character-encoding/security/advisories/GHSA-jqfh-8hw5-fqjr"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2021-39157"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/sonicdoe/detect-character-encoding/issues/15"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/sonicdoe/detect-character-encoding/commit/992a11007fff6cfd40b952150ab8d30410c4a20a"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/sonicdoe/detect-character-encoding"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/sonicdoe/detect-character-encoding/releases/tag/v0.7.0"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-755" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-08-24T19:11:52Z",
    "nvd_published_at" : "2021-08-24T19:15:00Z"
  }
}