CVE-2021-41126

Workarounds

• Reset the password of the deleted accounts to prevent them from signing in.

• Please contact [email protected] for code change instructions if you are unable to upgrade.

References

Credits to:
• Daniel Bidala

For more information

If you have any questions or comments about this advisory:

• Email us at [email protected]

Assuming an administrator once had previous access to the admin interface, they may still be able to sign in to the backend using October CMS v2.0.

The application does not adequately verify the identity of a user, device, or process before granting access. Typical impact: unauthorized access to functions or data reserved for authenticated parties.

CVE-2021-41126 has a CVSS score of 7.2 (High). The vector is network-reachable, high privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (2.1.12); upgrading removes the vulnerable code path.

Kodem intelligence

The issue has been patched in v2.1.12

1. What is CVE-2021-41126? CVE-2021-41126 is a high-severity improper authentication vulnerability in october/october (composer), affecting versions >= 2.1.0, < 2.1.12. It is fixed in 2.1.12. The application does not adequately verify the identity of a user, device, or process before granting access.
2. How severe is CVE-2021-41126? CVE-2021-41126 has a CVSS score of 7.2 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which packages are affected by CVE-2021-41126?
   • october/october (composer) (versions >= 2.1.0, < 2.1.12)
   • october/system (composer) (versions >= 2.1.0, < 2.1.12)
4. Is there a fix for CVE-2021-41126? Yes. CVE-2021-41126 is fixed in 2.1.12. Upgrade to this version or later.
5. Is CVE-2021-41126 exploitable, and should I be worried? Whether CVE-2021-41126 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2021-41126 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2021-41126?
   • Upgrade october/october to 2.1.12 or later
   • Upgrade october/system to 2.1.12 or later

Other vulnerabilities in october/october