CVE-2026-58654

The Grav API plugin (getgrav/grav-plugin-api) 1.0.0 contains an unrestricted file upload vulnerability in the avatar upload endpoint (/api/v1/users/user/avatar). The endpoint validates only the client-declared MIME type (getClientMediaType) beginning with 'image/' and does not inspect the actual file content or restrict the resulting extension, allowing an authenticated user to store arbitrary content — including PHP code, SVG with embedded JavaScript, and polyglot payloads — under user/accounts/avatars/ with predictable filenames. Direct HTTP access to the stored files is blocked by .htaccess (returns 403), but the files persist on disk and could lead to remote code execution or stored XSS in the presence of a path traversal flaw or server misconfiguration. Fixed in 1.0.1.

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/getgrav/grav/security/advisories/GHSA-xc64-vh46-vph6
https://www.vulncheck.com/advisories/grav-arbitrary-file-upload-via-avatar-endpoint
https://github.com/getgrav/grav/security/advisories/GHSA-xc64-vh46-vph6

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-08 14:17

Updated : 2026-07-08 18:16

NVD link : CVE-2026-58654

Mitre link : CVE-2026-58654

CVE.ORG link : CVE-2026-58654

JSON object : View

Products Affected

No product.

CWE

CWE-434

Unrestricted Upload of File with Dangerous Type

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