Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') Affecting node-handlebars package, versions <3:4.7.6+~4.1.0-2


Severity

Recommended
0.0
critical
0
10

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Threat Intelligence

EPSS
4.51% (91st percentile)

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  • Snyk IDSNYK-ECHOLATEST-NODEHANDLEBARS-20557230
  • published7 Oct 2026
  • disclosed4 May 2021

Introduced: 4 May 2021

CVE-2021-23383  (opens in a new tab)
CWE-1321  (opens in a new tab)

How to fix?

Upgrade Echo:latest node-handlebars to version 3:4.7.6+~4.1.0-2 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream node-handlebars package and not the node-handlebars package as distributed by Echo. See How to fix? for Echo:latest relevant fixed versions and status.

The package handlebars before 4.7.7 are vulnerable to Prototype Pollution when selecting certain compiling options to compile templates coming from an untrusted source.

CVSS Base Scores

version 3.1