Prototype Pollution

published 2022-04-12 4 y ago modified 2026-06-17 4 mo ago also GHSA-6xwr-q98w-rvg7 , EUVD-2022-1659

cvss: 7.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.8%; EPSS 1.8% chance of exploitation in 30 days, percentile 78%
public exploits: 0; none known

This affects the package nconf before 0.11.4. When using the memory engine, it is possible to store a nested JSON representation of the configuration. The .set() function, that is responsible for setting the configuration properties, is vulnerable to Prototype Pollution. By providing a crafted property, it is possible to modify the properties on the Object.prototype.

Patch / fix

fixed in 2 links 2

npm nconf 0.11.4
n/a nconf 0.11.4

github.com/indexzero/nconf#397 pull request
github.com/indexzero/nconf/releases/tag/v0.11.4 release

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2022-21803 updated 2026-07-03 cvss 7.3

nconf: Prototype pollution in memory store

Red Hat Advanced Cluster Management for Kubernetes 2 rhacm2/grc-ui-rhel8, openshift4/ose-console, rhacm2/grc-ui-api-rhel8, rhacm2/search-api-rhel8, rhacm2/application-ui-rhel8, rhacm2/kui-web-terminal-rhel8, +1 more
affected: no fix available

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

1.78% chance of exploitation in the next 30 days, higher than 78% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

snyk.io https://snyk.io/vuln/SNYK-JS-NCONF-2395478 referenced PoC, tagged "exploit" by a source, unverified
snyk.io https://snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-2632450 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	3.1	7.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P
CNA	3.1	7.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
NVD	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
NVD	2.0	5.0	AV:N/AC:L/Au:N/C:N/I:P/A:N
GitHub	3.1	7.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

Affected packages

ecosystem	package	affected	fixed in
npm	nconf	<0.11.4	0.11.4

Affected products

n/a nconf

Classification

Weakness

CWE-1321 Improperly Controlled Modification of Object Prototype Attributes

References

github.com /indexzero/nconf/pull/397
web, issue-tracking, patch, third-party-advisory
snyk.io /vuln/SNYK-JS-NCONF-2395478
web, exploit, third-party-advisory
snyk.io /vuln/SNYK-JAVA-ORGWEBJARSNPM-2632450
exploit, third-party-advisory
github.com /indexzero/nconf/releases/tag/v0.11.4
web, release-notes, third-party-advisory
nvd.nist.gov /vuln/detail/CVE-2022-21803
advisory
github.com /indexzero/nconf
package

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary