RCE in Express Handlebars Project

CVE-2021-32817

express-hbs is an Express handlebars template engine. express-hbs mixes pure template data with engine configuration options through the Express render API. More specifically, the layout parameter may trigger file disclosure vulnerabilities in downstream applications. This potential vulnerability is somewhat restricted in that only files with existing extentions (i.e. file.extension) can be included, files that lack an extension will have .hbs appended to them. For complete details refer to the referenced GHSL-2021-019 report. Notes in documentation have been added to help users of express-hbs avoid this potential information exposure vulnerability.

Vulnerability class: Information Disclosure

EPSS: 0.013 (66.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-32817?
CVE-2021-32817 is a medium-severity vulnerability in Express Handlebars Project, classified under Information Disclosure. CVSS score: 5.4/10. Published 2021-05-14.
How severe is CVE-2021-32817?
Medium severity. CVSS v3 base score is 5.4 out of 10.