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CVE-2021-21353

critical

Pug is an npm package which is a high-performance template engine.

Vendor / product: Pugjs — pug

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
9.0
9.0 (CVSS v3.1)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
Severity source: NVD CVSS v3.1 (nvd@nist.gov)
Timeline (UTC)
Published: 2021-03-03 02:15
Modified: 2026-11-02 18:18
NVD status: Analyzed
Last synced 1 day ago
Verified against the source API 2026-11-03 07:33 UTC
Exploitation
Not listed in CISA KEV (as of last catalog sync)
Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).

Affected products

pugjs / pug <3.0.1
pugjs / pug-code-gen <2.0.3, ≥3.0.0 <3.0.2

Weakness classification (CWE)

Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.

Mitigation & advisories

Patch / mitigation: https://github.com/pugjs/pug/commit/991e78f7c4220b2f8da042877c6f0ef5a4683be0
Patch / mitigation: https://github.com/pugjs/pug/issues/3312
Patch / mitigation: https://github.com/pugjs/pug/pull/3314
Patch / mitigation: https://github.com/pugjs/pug/commit/991e78f7c4220b2f8da042877c6f0ef5a4683be0
Patch / mitigation: https://github.com/pugjs/pug/issues/3312
Patch / mitigation: https://github.com/pugjs/pug/pull/3314

References

Data sources

NVD CVE API 2.0 — fetched 2026-11-03 07:33 UTC · record ↗

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