CVE-2021-21353: 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…

PriorityP260critical9CVSS 3.1

AVNACHPRNUINSCCHIHAH

EPSS

4.27%

89.9th percentile

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.

Affected

6 ranges

Vendor	Product	Version range	Fixed in
pugjs	pug	< 3.0.1	3.0.1
pugjs	pug	>= 0 < 3.0.1	3.0.1
pugjs	pug-code-gen	< 2.0.3	2.0.3
pugjs	pug-code-gen	>= 0 < 2.0.3	2.0.3
pugjs	pug-code-gen	>= 3.0.0 < 3.0.2	3.0.2
pugjs	pug-code-gen	>= 3.0.0 < 3.0.2	3.0.2

Detection & IOCsextracted from sources · hover to see the quote

→Attacker-controlled `pretty` option passed to the pug compiler enables RCE; monitor for user-supplied objects (e.g. query parameters) being spread into pug template inputs, particularly the `pretty` field. ↗
→Audit Node.js applications using the `pug` or `pug-code-gen` npm packages for versions prior to 3.0.1 (pug) or 2.0.3 (pug-code-gen) that accept untrusted input into the `pretty` compiler option. ↗
→The openshift-logging/kibana6-rhel8 container image is a known affected package; flag deployments of this image for patching. ↗

·The vulnerability is NOT exploitable if untrusted input cannot reach the `pretty` option of the pug compiler (e.g. templates are compiled in advance before user input is applied). ↗

CVSS provenance

nvdv3.19.0CRITICALCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H

nvdv2.06.8MEDIUMAV:N/AC:M/Au:N/C:P/I:P/A:P

vendor_redhat6.8MEDIUM

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