Vulnerability · Published Jul 20, 2026 · Assigned by VulnCheck

CVE-2026-57852Authentication Bypass via Null Short-Circuit in Grav CMS Scheduler Webhook Token Check

Medium 5.6

In plain English

A medium-severity security flaw in Grav CMS scheduler-webhook plugin from Trilby Media. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 53% of all known vulnerabilities).

Severity (CVSS 3.1)5.6Medium

Exploit odds (30 days)0.7%top 47.2% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

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.

Affected products (as reported)

Vendor	Product	Versions
Trilby Media	Grav CMS scheduler-webhook plugin	0 – through 1.1.30 – through 2.0.8

Weakness: CWE-303 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L

References

GitHub Security Advisory (GHSA-xwv3-2mv2-w33x) vendor-advisory
Product
https://www.vulncheck.com/advisories/authentication-bypass-via-null-short-circuit-in-grav-cms-scheduler-webhook-token-check third-party-advisory