CVE-2022-46175: json5 — Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')

Recommended actionWithin 7 days

High technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.

Patch available

What, why and how

JSON5 is an extension to the popular JSON file format that aims to be easier to write and maintain by hand (e.g. for config files). The `parse` method of the JSON5 library before and including versions 1.0.1 and 2.2.1 does not restrict parsing of keys named `__proto__`, allowing specially crafted strings to pollute the prototype of the resulting object. This vulnerability pollutes the prototype of the object returned by `JSON5.parse` and not the global Object prototype, which is the commonly understood definition of Prototype Pollution. However, polluting the prototype of a single object can have significant security impact for an application if the object is later used in trusted operations. This vulnerability could allow an attacker to set arbitrary and unexpected keys on the object returned from `JSON5.parse`. The actual impact will depend on how applications utilize the returned object and how they filter unwanted keys, but could include denial of service, cross-site scripting, elevation of privilege, and in extreme cases, remote code execution. `JSON5.parse` should restrict parsing of `__proto__` keys when parsing JSON strings to objects. As a point of reference, the `JSON.parse` method included in JavaScript ignores `__proto__` keys. Simply changing `JSON5.parse` to `JSON.parse` in the examples above mitigates this vulnerability. This vulnerability is patched in json5 versions 1.0.2, 2.2.2, and later.

What

Why

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

An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may execute code or commands in the affected security context.

What

Why

How

An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may execute code or commands in the affected security context.

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation

Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.

No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material

Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.

Reference recorded

A structured CVE source labels at least one public reference as exploit material. BlackTree has not independently validated that it is safe, reliable or weaponised.

Likely attack path: a network path → Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') → execute code or commands in the affected security context
Attack surface: Network
Privileges required: Low: a basic authenticated account is required
User interaction: None
Attack complexity: High: exploitation depends on specific conditions
Security boundary: Unchanged: impact remains within the vulnerable component's security authority
Weakness ? CWE means Common Weakness Enumeration: a standard category for the underlying weakness.: CWE-1321 ↗
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.
CVSS vector ? CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:H
Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.
AVNetworkAttack vector: The vulnerable component can be reached over a network.ACHighAttack complexity: Successful exploitation depends on specific conditions outside the attacker's direct control.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.ILowIntegrity impact: A successful attack can cause a limited loss.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land: After compromise, an attacker may use built-in shells, scripting engines, scheduled tasks and native network utilities for discovery, persistence or movement. This is a plausible LoTL path, not evidence that it has occurred for every attack.

NetworkRemote code executionPrivilege escalationDenial of serviceCWE-1321Public exploit reference

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

ENISA EUVD · EUVD-2022-7580Official EUVD mapping

0 linked advisory records.

Official EUVD record

BSI · German · WID-SEC-W-2024-3678Atlassian Confluence: Mehrere Schwachstellen

Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Atlassian Confluence ausnutzen, um einen Denial of Service Angriff durchzuführen, Daten zu manipulieren oder Sicherheitsvorkehrungen zu umgehen.

json5 — Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')

National CERT insights ?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

EUVD-2022-7580

What, why and how

Exploit reality and attack path

Official authority intelligence

Patch and workaround

Evidence and provenance

National CERT insights
?
CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.