Grav before 2.0.1 contains a decompression bomb vulnerability in ZipArchiver::extract() that lacks limits on uncompressed size, file count, and nesting depth. Attackers can supply a crafted ZIP archive that expands to fill available disk space, causing denial of service by exhausting storage resources.

grav-plugin-database is the database plugin for Grav CMS. Prior to 1.2.0, Database::__call builds PDO DSN strings by directly concatenating user-configurable YAML values from fields such as host, dbname, charset, server, database, directory, and filename without sanitization or validation, allowing an administrator with plugin configuration access to inject DSN attributes or path traversal values. This issue is fixed in version 1.2.0.

grav-plugin-database is the database plugin for Grav CMS. Prior to 1.2.0, the PDO::tableExists method interpolates its table argument directly into a raw SQL query string without sanitization, escaping, quoting, or whitelisting, allowing attacker-controlled table names passed by consuming plugin or developer code to execute arbitrary SQL against the configured database. This issue is fixed in version 1.2.0.

The Grav API plugin (getgrav/grav-plugin-api) before 1.0.3 fails to sanitize SVG files uploaded through the POST /api/v1/media endpoint. The HandlesMediaUploads::processUploadedFile() method validates only the file extension and never invokes Security::sanitizeSVG(), so an authenticated attacker with the api.media.write permission can upload an SVG containing arbitrary JavaScript. The file is stored unmodified and served with Content-Type: image/svg+xml; when an administrator opens it in a browser (directly or via <object>/<iframe>), the embedded script executes in their session context, enabling cookie theft and session hijacking.

Grav before 2.0.2 contains a Twig sandbox bypass that allows a page author (any admin.pages user, or anyone able to write to user/pages) to exfiltrate configuration secrets. Although the sandbox replaces the 'config' variable with a redacted facade and strips Config::get/toArray from the method allowlist, the raw container remains accessible via the allow-listed grav.offsetGet('config'), which returns the real Config object. Allow-listed object-dumping filters (json_encode, print_r, yaml_encode) then serialize that object at the PHP level without invoking the sandbox method gate, exposing the full config tree including plugin secrets such as SMTP credentials, API keys, and plugin DB credentials. This is an incomplete fix for GHSA-j274-39qw-32c9.

Grav is a file-based Web platform. Prior to 2.0.0, an authenticated admin.super user can crash Grav or fill the disk by uploading a specially crafted ZIP archive through the Direct Install tool because Installer::unZip calls ZipArchive::extractTo without limits on uncompressed size, entry count, or directory depth. This issue is fixed in version 2.0.0.

Grav is a file-based Web platform. Prior to 1.7.53, an authenticated administrator with backup permissions can download a ZIP archive containing the full Grav installation root, including user/accounts/admin.yaml with the administrator password hash and user/config with site configuration, through the backup download endpoint protected only by the session-static admin-nonce URL parameter. This issue is reported as fixed in version 1.7.53.

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.

Grav before 2.0.0 (affected through 2.0.0-rc.9 and the 2.0 branch) contains a stored CSS injection vulnerability in the Markdown image resize() media action. Prior media hardening rejects direct ?style= payloads and unsafe attribute() fallbacks, but the resize() action in Excerpts::processMediaActions() writes caller-controlled values directly into the image's styleAttributes. A lower-privileged content editor who can edit page Markdown can store a crafted image URL with semicolon-delimited CSS declarations in the resize parameters, which are rendered into the final <img style=...> attribute when a higher-privileged reviewer/admin views the page or preview. This does not require JavaScript execution but enables UI redress/overlay and content-manipulation attacks (e.g., a full-viewport fixed overlay). Fixed in 2.0.0.

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.