CVE-2021-21416: Potential sensitive information disclosed in error reports

Severity: low (CVSS 2.6 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-04-01 · updated 2026-06-17
Weakness: CWE-209

Description

django-registration is a user registration package for Django. The django-registration package provides tools for implementing user-account registration flows in the Django web framework. In django-registration prior to 3.1.2, the base user-account registration view did not properly apply filters to sensitive data, with the result that sensitive data could be included in error reports rather than removed automatically by Django. Triggering this requires: A site is using django-registration < 3.1.2, The site has detailed error reports (such as Django's emailed error reports to site staff/developers) enabled and a server-side error (HTTP 5xx) occurs during an attempt by a user to register an account. Under these conditions, recipients of the detailed error report will see all submitted data from the account-registration attempt, which may include the user's proposed credentials (such as a password).

Affected products

ubernostrum django-registration: before 3.1.2 — fixed in 3.1.2

How to fix

Upgrade to a fixed version: ubernostrum django-registration 3.1.2. Check the vendor advisory for mitigations.

References

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