Summary
Unauthenticated Craft CMS users can trigger a database backup
Unauthenticated users can trigger database backup operations the updater/backup action, potentially leading to resource exhaustion or information disclosure.
Users should update to the patched versions (5.8.21 and 4.16.17) to mitigate the issue.
Craft 3 users should update to the latest Craft 4 and 5 releases, which include the fixes.
References:
https://github.com/craftcms/cms/commit/f83d4e0c6b906743206b4747db4abf8164b8da39
https://github.com/craftcms/cms/blob/5.x/CHANGELOG.md#5821---2025-12-04
Affected Endpoints
POST /admin/actions/updater/backup(unauthenticated)
Vulnerability Details
Root Cause
All updater/* actions are explicitly configured with anonymous access:
// BaseUpdaterController.php
protected array|bool|int $allowAnonymous = self::ALLOW_ANONYMOUS_LIVE | self::ALLOW_ANONYMOUS_OFFLINE;
Attack Vector
- Send unauthenticated POST request to
/admin/actions/updater/backup - Database backup executes with configured
backupCommand
Impact
The application allocates resources such as memory, threads, or file descriptors based on untrusted input without enforcing a cap. Typical impact: resource exhaustion leading to denial of service.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
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. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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craftcms/cms to 5.8.21 or later; craftcms/cms to 4.16.17 or later
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is CVE-2025-68456? CVE-2025-68456 is a high-severity allocation of resources without limits or throttling vulnerability in craftcms/cms (composer), affecting versions >= 5.0.0-RC1, <= 5.8.20. It is fixed in 5.8.21, 4.16.17. The application allocates resources such as memory, threads, or file descriptors based on untrusted input without enforcing a cap.
- Which versions of craftcms/cms are affected by CVE-2025-68456? craftcms/cms (composer) versions >= 5.0.0-RC1, <= 5.8.20 is affected.
- Is there a fix for CVE-2025-68456? Yes. CVE-2025-68456 is fixed in 5.8.21, 4.16.17. Upgrade to this version or later.
- Is CVE-2025-68456 exploitable, and should I be worried? Whether CVE-2025-68456 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
- What actually determines whether CVE-2025-68456 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.
- How do I fix CVE-2025-68456?
- Upgrade
craftcms/cmsto 5.8.21 or later - Upgrade
craftcms/cmsto 4.16.17 or later
- Upgrade