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.
CVE-2026-57852
MEDIUMPre-NVD 5.65.6—Trending — 4 sources updated this week
EchelonGraph scoreHIGH confidence
Score 5.6 from GitHub Security Advisory published 2026-07-21. the CNA's CVSS baseline 5.6; sources differ by 0.0.
Triggered by: GitHub Security Advisory CVSS
Sources: cna:vulncheck, ghsa
5.6
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
- Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 5.6Exploit: NoneExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 5.6
- EG Score
- 5.6(high)
- EPSS
- 34.7%
- KEV
- Not listed
Published
July 20, 2026
Last Modified
July 21, 2026
Advisory Details (3)
Auto-updated Jul 20, 2026🔬 Proof of concept available. Patch available. Sources: github.
generic
Authentication Bypass via Null Short-Circuit in Grav CMS Scheduler Webhook Token Check | Advisories | VulnCheck
https://www.vulncheck.com/advisories/authentication-bypass-via-null-short-circuit-in-grav-cms-scheduler-webhook-token-checkgithub Patch Available🟡 PoC Available
Coordinated Vulnerability Disclosure - Trilby Media / Grav CMS · Advisory · getgrav/grav · GitHub
https://github.com/getgrav/grav/security/advisories/GHSA-xwv3-2mv2-w33xgeneric
GitHub - getgrav/grav: Modern, Crazy Fast, Ridiculously Easy and Amazingly Powerful Flat-File CMS powered by PHP, Markdown, Twig, and Symfony · GitHub
https://github.com/getgrav/gravVendor Advisories for CVE-2026-57852(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 8× in last 7d / 8× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-07-22 14:08 UTCEPSS rescore
- 2026-07-22 14:08 UTCEPSS rescore
- 2026-07-21 15:25 UTCEPSS rescore
- 2026-07-21 14:27 UTCEG score recompute
- 2026-07-21 14:27 UTCGHSA enrichment
- 2026-07-20 22:42 UTCEG score recompute
- 2026-07-20 22:12 UTCEG score recompute
- 2026-07-20 22:12 UTCMITRE cvelistV5first tracked
Frequently asked(5)
What is CVE-2026-57852?
CVE-2026-57852 is a medium vulnerability published on July 20, 2026. 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…
When was CVE-2026-57852 disclosed?
CVE-2026-57852 was first published in the National Vulnerability Database on July 20, 2026, with the most recent update on July 21, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-57852 actively exploited?
CVE-2026-57852 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 34.7% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-57852?
CVE-2026-57852 has a CVSS v3 base score of 5.6 (NVD).
How do I remediate CVE-2026-57852?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-57852, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-57852
Is Your Infrastructure Affected by CVE-2026-57852?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.