CVE-2020-7730: Bestzip Command Injection Vulnerability

CRITICAL
Advisory Identifier: GHSA-6xv6-jpvw-cx6q
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CVSS 9.8
CWE-78
Published
Advisory Summary

CVE-2020-7730 is a CRITICAL (CVSS 9.8) command injection vulnerability (CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')) affecting Bestzip libraries in the npm ecosystem. The issue involves command injection in bestzip. Remediation is available by upgrading affected packages to version 2.1.7.

CVE-2020-7730 at a Glance

CVE Identifier CVE-2020-7730
GHSA Identifier GHSA-6xv6-jpvw-cx6q
Severity CRITICAL
CVSS v3.1 Base Score 9.8
CWE Classification CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
Affected Product Bestzip
Package Ecosystem npm
Published Date
Last Updated

Security Impact

CVSS: 9.8

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:H/I:H/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 High (C:H)
Integrity High (I:H)
Availability High (A:H)

How to Fix CVE-2020-7730

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

bestzip fixed: 2.1.7 
npm install bestzip@2.1.7
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 bestzip

How to Check if You Are Affected

To determine whether your Node.js application is affected by CVE-2020-7730, inspect your project dependencies using npm:

npm ls bestzip

Analyze the terminal output to locate any version of Bestzip in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.1.7), your application is affected.

Note: The npm ls bestzip 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-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection'), where the product constructs all or part of an os command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended os command when it is sent to a downstream component. In Bestzip, 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

The package bestzip before 2.1.7 are vulnerable to Command Injection via the options param.

CVE-2020-7730 Affected Bestzip Versions

1 component(s)
Fixed Versions:
2.1.7
Product / Package Ecosystem Affected Versions Fixed Version
bestzip
npm/bestzip
npm
< 2.1.7
2.1.7

References

NVD — CVE-2020-7730 NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-7730
Security Fix Commit FIX COMMIT
https://github.com/nfriedly/node-bestzip/commit/45d4a901478c6a8f396c8b959dd6cf8fd3f955b6
snyk.io/vuln/snyk-js-bestzi... WEB
https://snyk.io/vuln/SNYK-JS-BESTZIP-609371

Frequently Asked Questions

What is CVE-2020-7730?
CVE-2020-7730 is a security vulnerability in Bestzip involving Command injection in bestzip under CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection').
Which Bestzip versions are affected?
Affected versions include releases prior to 2.1.7 across affected packages: bestzip.
What version fixes CVE-2020-7730?
Upgrading to 2.1.7 (or the latest patched release for your respective branch) resolves the vulnerability.
Is bestzip affected?
Yes, bestzip is affected in releases prior to 2.1.7. Upgrade your dependency to 2.1.7 or later.
What is the CVSS score of CVE-2020-7730?
CVE-2020-7730 has a CVSS v3.1 base score of 9.8 (CRITICAL) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
What CWE is associated with CVE-2020-7730?
CVE-2020-7730 is classified under CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') (The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.).
How can I check npm dependencies for CVE-2020-7730?
Run the dependency tree command: 'npm ls bestzip'. 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-6xv6-jpvw-cx6q",
  "modified" : "2021-05-04T22:37:03Z",
  "published" : "2021-05-06T18:27:36Z",
  "aliases" : [ "CVE-2020-7730" ],
  "summary" : "Command injection in bestzip",
  "details" : "The package bestzip before 2.1.7 are vulnerable to Command Injection via the options param.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "bestzip"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "2.1.7"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2020-7730"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/nfriedly/node-bestzip/commit/45d4a901478c6a8f396c8b959dd6cf8fd3f955b6"
  }, {
    "type" : "WEB",
    "url" : "https://snyk.io/vuln/SNYK-JS-BESTZIP-609371"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-78" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-05-04T22:37:03Z",
    "nvd_published_at" : "2020-09-04T10:15:00Z"
  }
}