CVE-2021-21353 MEDIUM

CVE-2021-21353: Remote code execution in pug

Vendor Pugjs
Product pug
Weakness CWE-74
Published March 3, 2021
Last update April 16, 2025

CVSS base score

6.8/10
Attack vector Network
Attack complexity High
Privileges required None
User interaction None
Confidentiality None
Integrity High

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:H/A:N

What the vulnerability does

01Description

Pug is an npm package which is a high-performance template engine. In pug before version 3.0.1, if a remote attacker was able to control the `pretty` option of the pug compiler, e.g. if you spread a user provided object such as the query parameters of a request into the pug template inputs, it was possible for them to achieve remote code execution on the node.js backend. This is fixed in version 3.0.1. This advisory applies to multiple pug packages including "pug", "pug-code-gen". pug-code-gen has a backported fix at version 2.0.3. This advisory is not exploitable if there is no way for un-trusted input to be passed to pug as the `pretty` option, e.g. if you compile templates in advance before applying user input to them, you do not need to upgrade.

Key dates

02Disclosure timeline

March 3, 2021 CVE published
April 16, 2025 Record updated