CVE-2026-16647: Drupal Disable Login Page cache invalidation bypass

CVE-2026-16647 · Severity: medium · CVSS 4.1 · Published 2026-09-02

The Disable Login Page module for Drupal is designed to block anonymous users from accessing the login form unless they provide a secret key. However, a cache invalidation flaw allows previously cached login pages to remain accessible even after login restrictions are enabled. An attacker can continue accessing the login page despite the protection being in place, potentially leading to unauthorized access attempts.

Technologies: Packagist:Https://Packages.Drupal.Org/8 Drupal/Disable Login. Vendors: Packagist:Https://Packages.Drupal.Org/8.

Quick answers

Is CVE-2026-16647 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-16647 being exploited in the wild.
How severe is CVE-2026-16647?
Medium severity, with a CVSS score of 4.1, published 2 September 2026.
Which products and versions are affected?
Packagist:Https://Packages.Drupal.Org/8 Drupal/Disable Login ECOSYSTEM:introduced=0,fixed=1.1.4.
Is there a fix for CVE-2026-16647?
Yes. Packagist:Https://Packages.Drupal.Org/8 Drupal/Disable Login: upgrade to 1.1.4 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-16647 attacked?
It is attacked over the network.
Am I affected by CVE-2026-16647?
Check whether you run Packagist:Https://Packages.Drupal.Org/8 Drupal/Disable Login or Zyxware Disable Login Page at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • Packagist:Https://Packages.Drupal.Org/8 Drupal/Disable Login: upgrade to 1.1.4 or later

Technical details

This is an authentication bypass vulnerability in the Disable Login Page Drupal module caused by improper cache handling. The module restricts access to /user/login by requiring a secret key parameter, but does not invalidate relevant caches when the restriction is enabled. As a result, previously cached responses containing the login page remain accessible to unauthenticated users indefinitely until caches are manually cleared. The vulnerability affects versions before 1.1.4 and is exploitable remotely without authentication. The fix requires upgrading to version 1.1.4 or later, which properly invalidates caches when login restrictions are activated.

Affected products

  • Drupal Disable Login Page 0.0.0 to 1.1.3

Identifiers

  • CVE-2026-16647
  • DRUPAL-CONTRIB-2026-111

Timeline

  • 2026-08-26: disclosed: Security advisory SA-CONTRIB-2026-111 published
  • 2026-08-26: patched: Version 1.1.4 released with fix
  • 2026-09-02: other: CVE-2026-16647 published on NVD

References

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