CVE-2026-57852

Grav CMS scheduler-webhook plugin contains an authentication bypass vulnerability that allows unauthenticated remote attackers to trigger configured scheduled jobs by exploiting a short-circuit logic flaw in the webhook token validation. Attackers can send a single unauthenticated POST request to the scheduler webhook endpoint to execute all configured scheduled jobs or target a specific job, causing unintended execution of operator-defined commands under the web server process user.

CVSS v3 5.6 MEDIUM

5.6^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/getgrav/grav
https://github.com/getgrav/grav/security/advisories/GHSA-xwv3-2mv2-w33x
https://www.vulncheck.com/advisories/authentication-bypass-via-null-short-circuit-in-grav-cms-scheduler-webhook-token-check

Configurations

No configuration.

History

20 Jul 2026, 22:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-20 22:17

Updated : 2026-07-21 18:57

NVD link : CVE-2026-57852

Mitre link : CVE-2026-57852

CVE.ORG link : CVE-2026-57852

JSON object : View

Products Affected

No product.

CWE

CWE-303

Incorrect Implementation of Authentication Algorithm

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