auth0-lock vulnerable to XSS via unsanitized placeholder property

Description

Auth0 Lock version 11.20.4 and earlier did not properly sanitize the generated HTML code. Customers using the additionalSignUpFields customization option to add a checkbox to the sign-up dialog that are passing a placeholder property obtained from an untrusted source (e.g.

Recommendation

Update the auth0-lock package to the latest compatible version. Followings are version details:

• Affected version(s): < 11.21.0
• Patched version(s): 11.21.0

References

• GHSA-w2pf-g6r8-pg22
• auth0.com
• CVE-2019-20174
• CWE-79
• CAPEC-310
• OWASP 2021-A3
• OWASP 2021-A6

Related Issues

• DOM-based XSS in auth0-lock - CVE-2020-15119
• Parse Server vulnerable to stored XSS via file upload of HTML-renderable file types - CVE-2026-31868
• Parse Server vulnerable to LDAP injection via unsanitized user input in DN and group filter construction - CVE-2026-31828
• Parse Server vulnerable to stored cross-site scripting (XSS) via SVG file upload - CVE-2026-30948

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Tags:

npm

auth0-lock