Vulnerability record · CVE-2021-21267 · published 19 March 2021
CVE-2021-21267: Schema-inspector project schema-inspector improper input validation vulnerability
SSchema Inspector Project · Schema Inspector
Schema-Inspector is an open-source tool to sanitize and validate JS objects (npm package schema-inspector). In before version 2.0.0, email address validation is vulnerable to a denial-of-service attack where some input (for example `a@0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.`) will freeze the program or web browser page executing the code. This affects any current schema-inspector users using any version to validate email addresses. Users who do not do email validation, and instead do other types of validation (like string min or max length, etc), are not affected. Users should upgrade to version 2.0.0, which uses a regex expression that isn't vulnerable to ReDoS.
Description
Schema-Inspector is an open-source tool to sanitize and validate JS objects (npm package schema-inspector). In before version 2.0.0, email address validation is vulnerable to a denial-of-service attack where some input (for example `a@0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.`) will freeze the program or web browser page executing the code. This affects any current schema-inspector users using any version to validate email addresses. Users who do not do email validation, and instead do other types of validation (like string min or max length, etc), are not affected. Users should upgrade to version 2.0.0, which uses a regex expression that isn't vulnerable to ReDoS.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
3 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
| Link | Tags |
|---|---|
| https://gist.github.com/mattwelke/b7f42424680a57b8161794ad1737cd8f | ExploitThird Party Advisory |
| https://github.com/schema-inspector/schema-inspector/security/advisories/GHSA-f38p-c2gq-4pmr | ExploitThird Party Advisory |
| https://security.netapp.com/advisory/ntap-20210528-0006/ | Third Party Advisory |
| https://www.npmjs.com/package/schema-inspector | ExploitThird Party Advisory |
| https://gist.github.com/mattwelke/b7f42424680a57b8161794ad1737cd8f | ExploitThird Party Advisory |
| https://github.com/schema-inspector/schema-inspector/security/advisories/GHSA-f38p-c2gq-4pmr | ExploitThird Party Advisory |
| https://security.netapp.com/advisory/ntap-20210528-0006/ | Third Party Advisory |
| https://www.npmjs.com/package/schema-inspector | ExploitThird Party Advisory |
Track CVE-2021-21267 inside VULONE
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Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2021-21267), CISA KEV, FIRST EPSS (scores of 2026-10-03). This page is refreshed as NVD updates the record.
