CVE-2021-29487

octobercms in a CMS platform based on the Laravel PHP Framework. In affected versions of the october/system package an attacker can exploit this vulnerability to bypass authentication and takeover of and user account on an October CMS server. The vulnerability is exploitable by unauthenticated users via a specially crafted request. This only affects frontend users and the attacker must obtain a Laravel secret key for cookie encryption and signing in order to exploit this vulnerability. The issue has been patched in Build 472 and v1.1.5.

octobercms in a CMS platform based on the Laravel PHP Framework. In affected versions of the october/system package an attacker can exploit this vulnerability to bypass authentication and takeover of and user account on an October CMS server. The vulnerability is exploitable by unauthenticated users via a specially crafted request. This only affects frontend users and the attacker must obtain a Laravel secret key for cookie encryption and signing in order to exploit this vulnerability. The issue has been patched in Build 472 and v1.1.5.

Impact

An attacker can exploit this vulnerability to bypass authentication using a specially crafted persist cookie.

• To exploit this vulnerability, an attacker must obtain a Laravel’s secret key for cookie encryption and signing.
• Due to the logic of how this mechanism works, a targeted user account must be logged in while the attacker is exploiting the vulnerability.
• Authorization via persist cookie not shown in access logs.

Patches

• Issue has been patched in Build 472 and v1.1.5
• Shortened patch instructions

Workarounds

Apply https://github.com/octobercms/library/commit/016a297b1bec55d2e53bc889458ed2cb5c3e9374 and https://github.com/octobercms/library/commit/5bd1a28140b825baebe6becd4f7562299d3de3b9 to your installation manually if you are unable to upgrade.

[Update 2022-01-20] Shortened patch instructions can be found here.

Recommendations

We recommend the following steps to make sure your server stays secure:

• Keep server OS and system software up to date.
• Keep October CMS software up to date.
• Use a multi-factor authentication plugin.
• Change the default backend URL or block public access to the backend area.
• Include the Roave/SecurityAdvisories Composer package to ensure that your application doesn't have installed dependencies with known security vulnerabilities.

References

Bugs found as part of Solar Security CMS Research. Credits to: • Andrey Basarygin • Andrey Guzei • Mikhail Khramenkov • Alexander Sidukov • Maxim Teplykh

For more information

If you have any questions or comments about this advisory:

• Email us at [email protected]

octobercms in a CMS platform based on the Laravel PHP Framework. In affected versions of the october/system package an attacker can exploit this vulnerability to bypass authentication and takeover of and user account on an October CMS server. The vulnerability is exploitable by unauthenticated users via a specially crafted request. This only affects frontend users and the attacker must obtain a Laravel secret key for cookie encryption and signing in order to exploit this vulnerability. The issue has been patched in Build 472 and v1.1.5.

octobercms in a CMS platform based on the Laravel PHP Framework. In affected versions of the october/system package an attacker can exploit this vulnerability to bypass authentication and takeover of and user account on an October CMS server. The vulnerability is exploitable by unauthenticated users via a specially crafted request. This only affects frontend users and the attacker must obtain a Laravel secret key for cookie encryption and signing in order to exploit this vulnerability. The issue has been patched in Build 472 and v1.1.5.

Impact

An attacker can exploit this vulnerability to bypass authentication using a specially crafted persist cookie.

• To exploit this vulnerability, an attacker must obtain a Laravel’s secret key for cookie encryption and signing.
• Due to the logic of how this mechanism works, a targeted user account must be logged in while the attacker is exploiting the vulnerability.
• Authorization via persist cookie not shown in access logs.

Patches

• Issue has been patched in Build 472 and v1.1.5
• Shortened patch instructions

Workarounds

Apply https://github.com/octobercms/library/commit/016a297b1bec55d2e53bc889458ed2cb5c3e9374 and https://github.com/octobercms/library/commit/5bd1a28140b825baebe6becd4f7562299d3de3b9 to your installation manually if you are unable to upgrade.

[Update 2022-01-20] Shortened patch instructions can be found here.

Recommendations

We recommend the following steps to make sure your server stays secure:

• Keep server OS and system software up to date.
• Keep October CMS software up to date.
• Use a multi-factor authentication plugin.
• Change the default backend URL or block public access to the backend area.
• Include the Roave/SecurityAdvisories Composer package to ensure that your application doesn't have installed dependencies with known security vulnerabilities.

References

Bugs found as part of Solar Security CMS Research. Credits to: • Andrey Basarygin • Andrey Guzei • Mikhail Khramenkov • Alexander Sidukov • Maxim Teplykh

For more information

If you have any questions or comments about this advisory:

• Email us at [email protected]