Vulnerability · Published Jul 8, 2026 · Assigned by VulnCheck

CVE-2026-58656Grav API Plugin - Cross-Origin Admin Account Takeover via CORS Wildcard and JWT Query Parameter

High 7.5

In plain English

A high-severity security flaw in grav from getgrav. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 29% of all known vulnerabilities).

Severity (CVSS 3.1)7.5High

Exploit odds (30 days)0.4%top 70.7% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

Grav API plugin before v1.0.0-rc.16 accepts JWT tokens via the ?token= URL query parameter and responds with Access-Control-Allow-Origin: *, allowing unauthenticated attackers to make fully authenticated cross-origin API requests from any malicious website. Attackers who obtain a leaked JWT token from access logs, proxy logs, browser history, or Referrer headers can create persistent backdoor super-admin accounts and exfiltrate sensitive configuration and user data.

Affected products (as reported)

Vendor	Product	Versions
getgrav	grav	0 – through 1.0.0-rc.15

Weakness: CWE-598 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

References

GitHub Security Advisory (GHSA-hqm9-5xxw-4qxp) vendor-advisory
VulnCheck Advisory: Grav API Plugin - Cross-Origin Admin Account Takeover via CORS Wildcard and JWT Query Parameter third-party-advisory