Prototype Pollution

published 2022-01-28 4 y ago modified 2026-06-17 4 mo ago also GHSA-9fp7-4fjm-q3mf , EUVD-2022-0939

cvss: 5.6; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.7%; EPSS 1.7% chance of exploitation in 30 days, percentile 77%
public exploits: 0; none known

The package keyget from 0.0.0 are vulnerable to Prototype Pollution via the methods set, push, and at which could allow an attacker to cause a denial of service and may lead to remote code execution. **Note:** This vulnerability derives from an incomplete fix to [CVE-2020-28272](https://security.snyk.io/vuln/SNYK-JS-KEYGET-1048048)

Exploit prediction

1.68% chance of exploitation in the next 30 days, higher than 77% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

snyk.io https://snyk.io/vuln/SNYK-JS-KEYGET-2342624 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.6	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P
CNA	3.1	5.6	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L
NVD	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	7.5	AV:N/AC:L/Au:N/C:P/I:P/A:P
GitHub	3.1	5.6	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L

Affected packages

ecosystem	package	affected	fixed in
npm	keyget	<=2.4.0	no fix listed

Classification

Weakness

CWE-1321 Improperly Controlled Modification of Object Prototype Attributes

References

snyk.io /vuln/SNYK-JS-KEYGET-2342624
web, exploit, third-party-advisory
nvd.nist.gov /vuln/detail/CVE-2021-23760
advisory
github.com /rumkin/keyget
package
security.snyk.io /vuln/SNYK-JS-KEYGET-1048048
web

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