HighGHSA-q42p-pg8m-cqh6

Prototype Pollution in handlebars

Published 5 Jun 2019 · Updated 10 Sept 2026

Affected packages

handlebarsnpm

Affected: >=4.1.0 <4.1.2
Fixed in: 4.1.2

Update to the fixed version for your release line, for example:npm install handlebars@4.1.2

handlebarsnpm

Affected: >=4.0.0 <4.0.14
Fixed in: 4.0.14

Update to the fixed version for your release line, for example:npm install handlebars@4.0.14

handlebarsnpm

Affected: <3.0.7
Fixed in: 3.0.7

Update to the fixed version for your release line, for example:npm install handlebars@3.0.7

Details

Versions of handlebars prior to 4.0.14 are vulnerable to Prototype Pollution. Templates may alter an Objects' prototype, thus allowing an attacker to execute arbitrary code on the server.

Recommendation

For handlebars 4.1.x upgrade to 4.1.2 or later. For handlebars 4.0.x upgrade to 4.0.14 or later.

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References

Advisory data from OSV.dev (opens OSV.dev in a new tab), refreshed daily.