CVE-2021-21353 (GCVE-0-2021-21353)
Vulnerability from cvelistv5 – Published: 2021-03-03 01:50 – Updated: 2026-11-02 17:59
VLAI
EPSS
VEX
Title
Remote code execution in pug
Summary
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.
Severity
6.8 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-11-02 17:59 UTC
CWE
- CWE-74 - Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
Assigner
GitHub_M
CNA
References
7 references
| URL | Tags |
|---|---|
| https://github.com/pugjs/pug/security/advisories/… | x_refsource_CONFIRM |
| https://github.com/pugjs/pug/issues/3312 | x_refsource_MISC |
| https://github.com/pugjs/pug/pull/3314 | x_refsource_MISC |
| https://github.com/pugjs/pug/commit/991e78f7c4220… | x_refsource_MISC |
| https://github.com/pugjs/pug/releases/tag/pug%403.0.1 | x_refsource_MISC |
| https://www.npmjs.com/package/pug | x_refsource_MISC |
| https://www.npmjs.com/package/pug-code-gen | x_refsource_MISC |
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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