How severe is GHSA-m9hw-7xfv-wqg7?

No CVSS score has been assigned to GHSA-m9hw-7xfv-wqg7 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by GHSA-m9hw-7xfv-wqg7?

GHSA-m9hw-7xfv-wqg7 affects the following packages: json-logic-js (npm). Ecosystems affected: npm.

How do I fix GHSA-m9hw-7xfv-wqg7?

Update json-logic-js to 2.0.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-m9hw-7xfv-wqg7 is resolved across your whole dependency graph.

How do I detect GHSA-m9hw-7xfv-wqg7 in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for json-logic-js, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate GHSA-m9hw-7xfv-wqg7 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Is GHSA-m9hw-7xfv-wqg7 actively exploited in the wild?

No public exploit code has been indexed for GHSA-m9hw-7xfv-wqg7 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

When was GHSA-m9hw-7xfv-wqg7 published, and has it been updated?

GHSA-m9hw-7xfv-wqg7 was published on November 12, 2020 and was last updated on November 12, 2020. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

Prototype Pollution in json-logic-js

Real-World Exposure

1 pkg affected

How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.

394other npm packages depend on this — each one inherits the vulnerability until it's patched upstream

json-logic-jsnpm

3.7Mdownloads / week

Description

Versions of json-logic-js prior to 2.0.0 are vulnerable to Prototype Pollution. The method operation allows a malicious user to modify the prototype of Object through the method property name. This causes modification of any existing property that will exist on all objects and leads to Remote Code Execution.

The following rule creates a popup when run from a browser:

{
  "method": [
    {
      "method": [
        {
          "var": "__proto__.constructor.is.__proto__"
        },
        "constructor",
        [
          "var x = 'SECURITY!'; console.log(x, window.fetch); alert(x)"
        ]
      ]
    },
    "call"
  ]
}

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`json-logic-js`	all versions	2.0.0`npm install json-logic-js@2.0.0`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for json-logic-js, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update json-logic-js to 2.0.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-m9hw-7xfv-wqg7 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Frequently Asked Questions

Versions of json-logic-js prior to 2.0.0 are vulnerable to Prototype Pollution. The method operation allows a malicious user to modify the prototype of Object through the method property name. This causes modification of any existing property that will exist on all objects and leads to Remote Code Execution. The following rule creates a popup when run from a browser: ``` { "method": [ { "method": [ { "var": "__proto__.constructor.is.__proto__" }, "constructor", [ "var x = 'SECURITY!'; console.log(x, window.fetch); alert(x)"

O3 Security · Impact-Aware SCA

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Prototype Pollution in json-logic-jsGHSA-m9hw-7xfv-wqg7