Grav API Plugin up to 1.0.0 Avatar Upload Endpoint avatar unrestricted upload

Summaryinfo

A vulnerability labeled as critical has been found in Grav API Plugin up to 1.0.0. This affects an unknown part of the file /api/v1/users/user/avatar of the component Avatar Upload Endpoint. Such manipulation leads to unrestricted upload. This vulnerability is uniquely identified as CVE-2026-58654. The attack can be launched remotely. No exploit exists.

Detailsinfo

A vulnerability was found in Grav API Plugin up to 1.0.0 and classified as critical. Affected by this issue is an unknown part of the file /api/v1/users/user/avatar of the component Avatar Upload Endpoint. The manipulation with an unknown input leads to a unrestricted upload vulnerability. Using CWE to declare the problem leads to CWE-434. The product allows the attacker to upload or transfer files of dangerous types that can be automatically processed within the product's environment. Impacted is confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-58654 since 07/01/2026. The exploitation is known to be easy. The attack may be launched remotely. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1608.002 by the MITRE ATT&CK project.

Upgrading to version 1.0.1 eliminates this vulnerability.

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Productinfo

Type

• Automation Software

Vendor

• Grav

Name

• API Plugin

Version

• 1.0

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

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