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Vulnerability record · CVE-2019-20922 · published 30 September 2020

CVE-2019-20922: Handlebarsjs handlebars uncontrolled resource consumption vulnerability

Handlebarsjs · Handlebars

Handlebars before 4.4.5 allows Regular Expression Denial of Service (ReDoS) because of eager matching. The parser may be forced into an endless loop while processing crafted templates. This may allow attackers to exhaust system resources.

7.5 CVSS 3.1 High EPSS 3.7% · top 10.7% CWE-400 · Uncontrolled resource consumption
7.5CVSS 3.1 base score, v2 7.8
3.7%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
6References
17 Jun 2026Last modified by NVD

Description

Handlebars before 4.4.5 allows Regular Expression Denial of Service (ReDoS) because of eager matching. The parser may be forced into an endless loop while processing crafted templates. This may allow attackers to exhaust system resources.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://github.com/handlebars-lang/handlebars.js/commit/8d5530ee2c3ea9f0aee3fde310b9f36887d00b8b PatchThird Party Advisory
https://snyk.io/vuln/SNYK-JS-HANDLEBARS-480388 Third Party Advisory
https://www.npmjs.com/advisories/1300 Third Party Advisory
https://github.com/handlebars-lang/handlebars.js/commit/8d5530ee2c3ea9f0aee3fde310b9f36887d00b8b PatchThird Party Advisory
https://snyk.io/vuln/SNYK-JS-HANDLEBARS-480388 Third Party Advisory
https://www.npmjs.com/advisories/1300 Third Party Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2019-20922), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.