CVE-2021-21353
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…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (4.30%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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.
- CVSS 3.1
- 9.0 CRITICALCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
- EPSS
- 4.30% probability · 91th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-74, CWE-94
- Affected
- pugjs/pug · pugjs/pug-code-gen
- Source
- security-advisories@github.com
EPSS 4.3% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://github.com/pugjs/pug/commit/991e78f7c4220b2f8da042877c6f0ef5a4683be0Patch, Third Party Advisory
- https://github.com/pugjs/pug/issues/3312Exploit, Patch, Third Party Advisory
- https://github.com/pugjs/pug/pull/3314Patch, Third Party Advisory
- https://github.com/pugjs/pug/releases/tag/pug%403.0.1Release Notes, Third Party Advisory
- https://github.com/pugjs/pug/security/advisories/GHSA-p493-635q-r6grThird Party Advisory
- https://www.npmjs.com/package/pugProduct, Third Party Advisory
- https://www.npmjs.com/package/pug-code-genProduct, Third Party Advisory
- https://github.com/pugjs/pug/commit/991e78f7c4220b2f8da042877c6f0ef5a4683be0Patch, Third Party Advisory
- https://github.com/pugjs/pug/issues/3312Exploit, Patch, Third Party Advisory
- https://github.com/pugjs/pug/pull/3314Patch, Third Party Advisory
- https://github.com/pugjs/pug/releases/tag/pug%403.0.1Release Notes, Third Party Advisory
- https://github.com/pugjs/pug/security/advisories/GHSA-p493-635q-r6grThird Party Advisory
- https://www.npmjs.com/package/pugProduct, Third Party Advisory
- https://www.npmjs.com/package/pug-code-genProduct, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.