CyberSecBulletin
CVE-2022-4742NVD status: Modified

json-pointer: Improperly Controlled Modification of Object Prototype Attributes

Published Updated By the CyberSecBulletin desk

CVE-2022-4742 is a critical-severity improperly controlled modification of object prototype attributes vulnerability in json-pointer, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected json-pointer versions: 0.6.0; 0.6.1. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.1% chance of exploitation within 30 days, higher than 66% of scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of json-pointer you run against the affected versions below, and install the vendor's latest release.
  2. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Json-pointerjson-pointer0.6.0; 0.6.1Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.16.3MediumCNA (vuldb.com)
CVSS 3.19.8CriticalNVD
CVSS 2.06.5MediumCNA (vuldb.com)

Official description

A vulnerability, which was classified as critical, has been found in json-pointer up to 0.6.1. Affected by this issue is the function set of the file index.js. The manipulation leads to improperly controlled modification of object prototype attributes ('prototype pollution'). The attack may be launched remotely. Upgrading to version 0.6.2 is able to address this issue. The patch is identified as 859c9984b6c407fc2d5a0a7e47c7274daa681941. It is recommended to upgrade the affected component. VDB-216794 is the identifier assigned to this vulnerability.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improperly Controlled Modification of Object Prototype Attributes

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 developers prevent this class of flaw

  • By freezing the object prototype first (for example, Object.freeze(Object.prototype)), modification of the prototype becomes impossible.
  • By blocking modifications of attributes that resolve to object prototype, such as proto or prototype, this weakness can be mitigated.
  • When handling untrusted objects, validating using a schema can be used.

More Improperly Controlled Modification of Object Prototype Attributes vulnerabilities (CWE-1321)

Timeline

  1. CVE record published.
  2. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Recent Improperly Controlled Modification of Object Prototype Attributes vulnerabilities

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