Vulnerabilities in pkg:npm/deobfuscator

PACKAGE
Advisory Identifier: GHSA-jg82-xh3w-rhxx
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Advisory Summary

CVE-2023-45811 is a HIGH (CVSS 7.8) synchrony deobfuscator prototype pollution vulnerability vulnerability (CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')) affecting Deobfuscator libraries in the npm ecosystem. The issue involves synchrony deobfuscator prototype pollution vulnerability leading to arbitrary code execution. Remediation is available by upgrading affected packages to version 2.4.4.

1 Known Advisory Record(s)
Package Vulnerability Intelligence

pkg:npm/deobfuscator

1 Known Advisory Record(s)

Vulnerability advisories affecting package pkg:npm/deobfuscator. Select an advisory below to view technical details or fixes.

Advisory ID CVE / NVD Severity Summary
GHSA-jg82-xh3w-rhxx CVE-2023-45811 HIGH Synchrony deobfuscator prototype pollution vulnerability leading to arbitrary code execution

CVE-2023-45811 at a Glance

CVE Identifier CVE-2023-45811
GHSA Identifier GHSA-jg82-xh3w-rhxx
Severity HIGH
CVSS v3.1 Base Score 7.8
CWE Classification CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')
Affected Product Deobfuscator
Package Ecosystem npm
Published Date
Last Updated

Security Impact

CVSS: 7.8

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

Attack Vector Local (AV:L)
Attack Complexity Low (AC:L)
Privileges Required Low (PR:L)
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-2023-45811

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

deobfuscator fixed: 2.4.4 
npm install deobfuscator@2.4.4
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 deobfuscator

How to Check if You Are Affected

To determine whether your Node.js application is affected by CVE-2023-45811, inspect your project dependencies using npm:

npm ls deobfuscator

Analyze the terminal output to locate any version of Deobfuscator in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.4.4), your application is affected.

Note: The npm ls deobfuscator 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-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution'), where the product receives input from an upstream component that specifies attributes that are to be initialized or updated in an object, but it does not properly control modifications of attributes of the object prototype. In Deobfuscator, 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 `__proto__` pollution vulnerability exists in synchrony versions before v2.4.4. Successful exploitation could lead to arbitrary code execution. ### Summary A `__proto__` pollution vulnerability exists in the [LiteralMap] transformer allowing crafted input to modify properties in the Object prototype. When executing in Node.js, due to use of the `prettier` module, defining a `parser` property on `__proto__` with a path to a JS module on disk [causes a `require` of the value][prettier/src/main/parser.js] which can lead to arbitrary code execution. ### Patch A fix has been released in `deobfuscator@2.4.4`. ### Mitigation - Upgrade synchrony to v2.4.4 - Launch node with the [--disable-proto=delete][disable-proto] or [--disable-proto=throw][disable-proto] flag ### Proof of Concept Craft a malicious input file named `poc.js` as follows: ```js // Malicious code to be run after this file is imported. Logs the result of shell command "dir" to the console. console.log(require('child_process').execSync('dir').toString()) // Synchrony exploit PoC { var __proto__ = { parser: 'poc.js' } } ``` Then, run `synchrony poc.js` from the same directory as the malicious file. ### Credits This vulnerability was found and disclosed by [William Khem-Marquez][SteakEnthusiast]. [LiteralMap]: src/transformers/literalmap.ts [SteakEnthusiast]: https://github.com/SteakEnthusiast [disable-proto]: https://nodejs.dev/en/api/v20/cli/#--disable-protomode [prettier/src/main/parser.js]: https://github.com/prettier/prettier/blob/2.5.1/src/main/parser.js#L53-L63

CVE-2023-45811 Affected Deobfuscator Versions

1 component(s)
Fixed Versions:
2.4.4
Product / Package Ecosystem Affected Versions Fixed Version
deobfuscator
npm/deobfuscator
npm
≥ 2.0.1
< 2.4.4
2.4.4

References

GitHub Advisory / Wiki ADVISORY
https://github.com/relative/synchrony/security/advisories/GHSA-jg82-xh3w-rhxx
NVD — CVE-2023-45811 NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-45811
Security Fix Commit FIX COMMIT
https://github.com/relative/synchrony/commit/b583126be94c4db7c5a478f1c5204bfb4162cf40
Deobfuscator Source Repository REPOSITORY
https://github.com/relative/synchrony
GitHub Advisory / Wiki ADVISORY
https://github.com/relative/synchrony/security/advisories/src/transformers/literalmap.ts

Frequently Asked Questions

What is CVE-2023-45811?
CVE-2023-45811 is a security vulnerability in Deobfuscator involving Synchrony deobfuscator prototype pollution vulnerability leading to arbitrary code execution under CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution').
Which Deobfuscator versions are affected?
Affected versions include releases prior to 2.4.4 across affected packages: deobfuscator.
What version fixes CVE-2023-45811?
Upgrading to 2.4.4 (or the latest patched release for your respective branch) resolves the vulnerability.
Is deobfuscator affected?
Yes, deobfuscator is affected in releases prior to 2.4.4. Upgrade your dependency to 2.4.4 or later.
What is the CVSS score of CVE-2023-45811?
CVE-2023-45811 has a CVSS v3.1 base score of 7.8 (HIGH) with vector string CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
What CWE is associated with CVE-2023-45811?
CVE-2023-45811 is classified under CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') (The product receives input from an upstream component that specifies attributes that are to be initialized or updated in an object, but it does not properly control modifications of attributes of the object prototype.).
How can I check npm dependencies for CVE-2023-45811?
Run the dependency tree command: 'npm ls deobfuscator'. 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-jg82-xh3w-rhxx",
  "modified" : "2025-07-22T15:37:30Z",
  "published" : "2023-10-18T18:27:13Z",
  "aliases" : [ "CVE-2023-45811" ],
  "summary" : "Synchrony deobfuscator prototype pollution vulnerability leading to arbitrary code execution",
  "details" : "### Impact\n\nA `__proto__` pollution vulnerability exists in synchrony versions before v2.4.4. Successful exploitation could lead to arbitrary code execution.\n\n### Summary\n\nA `__proto__` pollution vulnerability exists in the [LiteralMap] transformer allowing crafted input to modify properties in the Object prototype.\n\nWhen executing in Node.js, due to use of the `prettier` module, defining a `parser` property on `__proto__` with a path to a JS module on disk [causes a `require` of the value][prettier/src/main/parser.js] which can lead to arbitrary code execution.\n\n### Patch\n\nA fix has been released in `deobfuscator@2.4.4`.\n\n### Mitigation\n\n- Upgrade synchrony to v2.4.4\n- Launch node with the [--disable-proto=delete][disable-proto] or [--disable-proto=throw][disable-proto] flag\n\n### Proof of Concept\n\nCraft a malicious input file named `poc.js` as follows:\n\n```js\n// Malicious code to be run after this file is imported. Logs the result of shell command \"dir\" to the console.\nconsole.log(require('child_process').execSync('dir').toString())\n\n// Synchrony exploit PoC\n{\n  var __proto__ = { parser: 'poc.js' }\n}\n```\n\nThen, run `synchrony poc.js` from the same directory as the malicious file.\n\n### Credits\n\nThis vulnerability was found and disclosed by [William Khem-Marquez][SteakEnthusiast].\n\n[LiteralMap]: src/transformers/literalmap.ts\n[SteakEnthusiast]: https://github.com/SteakEnthusiast\n[disable-proto]: https://nodejs.dev/en/api/v20/cli/#--disable-protomode\n[prettier/src/main/parser.js]: https://github.com/prettier/prettier/blob/2.5.1/src/main/parser.js#L53-L63",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "deobfuscator"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "2.0.1"
      }, {
        "fixed" : "2.4.4"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/relative/synchrony/security/advisories/GHSA-jg82-xh3w-rhxx"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2023-45811"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/relative/synchrony/commit/b583126be94c4db7c5a478f1c5204bfb4162cf40"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/relative/synchrony"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/relative/synchrony/security/advisories/src/transformers/literalmap.ts"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-1321" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2023-10-18T18:27:13Z",
    "nvd_published_at" : "2023-10-17T23:15:12Z"
  }
}