CVE-2026-72697

Grav CMS before 2.0.16 contains a path traversal vulnerability in the media_directory() Twig function that fails to validate filesystem paths, allowing authenticated users to enumerate and access files outside intended scope. Attackers with page authoring privileges can supply arbitrary filesystem paths to media_directory() and use the allow-listed filepath accessor on Medium objects to read file contents of any file matching configured media extensions that the web server process can access.

Grav CMS before 2.0.16 contains a path traversal vulnerability in the media_directory() Twig function that fails to validate filesystem paths, allowing authenticated users to enumerate and access files outside intended scope. Attackers with page authoring privileges can supply arbitrary filesystem paths to media_directory() and use the allow-listed filepath accessor on Medium objects to read file contents of any file matching configured media extensions that the web server process can access.

Summary

The media_directory() Twig function is allow-listed for use in sandboxed, editor-authored page content (system/config/security.yaml). Its implementation, GravExtension::mediaDirFunc(), only treats the input as unsafe when it looks like a Grav stream (user://, theme://, etc). If the input is instead a plain filesystem path, absolute or relative, the stream check is skipped entirely and the raw string is handed straight to new Media($media_dir), which lists every file in that directory whose extension matches a configured media type (which by default includes txt, json, xml, pdf, doc, docx, and more, not just images) and builds Medium objects for them.

Separately, the sandbox's own allow-list for the Medium class includes the filepath accessor. A code comment directly above that allow-list entry states the developers' intent was for filepath to be part of the "dangerous surface" that "stays blocked", but it is listed as an allowed method on the very same line, contradicting that stated intent.

Combined, a user who can enter page content that gets processed as Twig (process.twig: true in frontmatter, or any modular page, which is unsandboxed and unconditional per the code comment in processPage()) can point media_directory() at any directory the web server process can read, anywhere on the filesystem, and both enumerate and read the content of any file in it whose extension is a recognized media type.

Affected product and version

Product: Grav CMS, getgrav/grav Confirmed present in: 2.0.15, commit c2b46866857a93a0aa7048e7ed707ed3ed45dbc3

Affected code

system/src/Grav/Common/Twig/Extension/GravExtension.php, mediaDirFunc():

public function mediaDirFunc($media_dir)
{
    /** @var UniformResourceLocator $locator */
    $locator = $this->grav['locator'];

    if ($locator->isStream($media_dir)) {
        $media_dir = $locator->findResource($media_dir);
    }

    if ($media_dir && file_exists($media_dir)) {
        return new Media($media_dir);
    }

    return null;
}

There is no check that $media_dir, when it is not a recognized stream, is contained within any site-relative root. It is used exactly as supplied.

system/src/Grav/Common/Page/Media.php, init(), called from the constructor:

protected function init()
{
    $path = $this->getPath();

    // Handle special cases where page doesn't exist in filesystem.
    if (!$path || !is_dir($path)) {
        return;
    }
    ...
    $iterator = new FilesystemIterator($path, FilesystemIterator::UNIX_PATHS | FilesystemIterator::SKIP_DOTS);

    foreach ($iterator as $file => $info) {
        ...
        [$basename, $ext, $type, $extra] = $this->getFileParts($filename);
        if (!in_array(strtolower((string) $ext), $media_types, true)) {
            continue;
        }
        ...
    }

$path here is whatever was passed to the Media constructor, the raw, unvalidated string from mediaDirFunc().

system/config/security.yaml, the Medium sandbox allow-list and the comment directly above it:

    # ...
    # dangerous surface (save, set, copy, deleteFile, toArray, filepath, …) is
    # absent from ALLOWED_ACTIONS and stays blocked.
    - class: 'Grav\Common\Page\Medium\Medium'
      methods: 'url, html, filepath, filename, metadata, srcset, parsedownelement, __tostring, @media_actions'

filepath is named in the comment as something that is supposed to stay blocked, and is then listed as an allowed method one line later.

media_directory in the sandbox's function allow-list:

    - media_directory

Root cause

Two gaps, and the second one converts the first from "list filenames from a directory" into "read the content of files":

1. mediaDirFunc()'s containment check only fires for recognized Grav streams. A plain filesystem path, which is the normal, documented shape of a string, is not a stream by definition, so it always takes the unchecked path.
2. Once a…

Duplicate Advisory

This advisory has been withdrawn because it is a duplicate of GHSA-47ch-6w46-6xm7. This link is maintained to preserve external references.

Original Description

Grav CMS before 2.0.16 contains a path traversal vulnerability in the media_directory() Twig function that fails to validate filesystem paths, allowing authenticated users to enumerate and access files outside intended scope. Attackers with page authoring privileges can supply arbitrary filesystem paths to media_directory() and use the allow-listed filepath accessor on Medium objects to read file contents of any file matching configured media extensions that the web server process can access.

Grav CMS before 2.0.16 contains a path traversal vulnerability in the media_directory() Twig function that fails to validate filesystem paths, allowing authenticated users to enumerate and access files outside intended scope. Attackers with page authoring privileges can supply arbitrary filesystem paths to media_directory() and use the allow-listed filepath accessor on Medium objects to read file contents of any file matching configured media extensions that the web server process can access.

Grav CMS before 2.0.16 contains a path traversal vulnerability in the media_directory() Twig function that fails to validate filesystem paths, allowing authenticated users to enumerate and access files outside intended scope. Attackers with page authoring privileges can supply arbitrary filesystem paths to media_directory() and use the allow-listed filepath accessor on Medium objects to read file contents of any file matching configured media extensions that the web server process can access.

Summary

The media_directory() Twig function is allow-listed for use in sandboxed, editor-authored page content (system/config/security.yaml). Its implementation, GravExtension::mediaDirFunc(), only treats the input as unsafe when it looks like a Grav stream (user://, theme://, etc). If the input is instead a plain filesystem path, absolute or relative, the stream check is skipped entirely and the raw string is handed straight to new Media($media_dir), which lists every file in that directory whose extension matches a configured media type (which by default includes txt, json, xml, pdf, doc, docx, and more, not just images) and builds Medium objects for them.

Separately, the sandbox's own allow-list for the Medium class includes the filepath accessor. A code comment directly above that allow-list entry states the developers' intent was for filepath to be part of the "dangerous surface" that "stays blocked", but it is listed as an allowed method on the very same line, contradicting that stated intent.

Combined, a user who can enter page content that gets processed as Twig (process.twig: true in frontmatter, or any modular page, which is unsandboxed and unconditional per the code comment in processPage()) can point media_directory() at any directory the web server process can read, anywhere on the filesystem, and both enumerate and read the content of any file in it whose extension is a recognized media type.

Affected product and version

Product: Grav CMS, getgrav/grav Confirmed present in: 2.0.15, commit c2b46866857a93a0aa7048e7ed707ed3ed45dbc3

Affected code

system/src/Grav/Common/Twig/Extension/GravExtension.php, mediaDirFunc():

public function mediaDirFunc($media_dir)
{
    /** @var UniformResourceLocator $locator */
    $locator = $this->grav['locator'];

    if ($locator->isStream($media_dir)) {
        $media_dir = $locator->findResource($media_dir);
    }

    if ($media_dir && file_exists($media_dir)) {
        return new Media($media_dir);
    }

    return null;
}

There is no check that $media_dir, when it is not a recognized stream, is contained within any site-relative root. It is used exactly as supplied.

system/src/Grav/Common/Page/Media.php, init(), called from the constructor:

protected function init()
{
    $path = $this->getPath();

    // Handle special cases where page doesn't exist in filesystem.
    if (!$path || !is_dir($path)) {
        return;
    }
    ...
    $iterator = new FilesystemIterator($path, FilesystemIterator::UNIX_PATHS | FilesystemIterator::SKIP_DOTS);

    foreach ($iterator as $file => $info) {
        ...
        [$basename, $ext, $type, $extra] = $this->getFileParts($filename);
        if (!in_array(strtolower((string) $ext), $media_types, true)) {
            continue;
        }
        ...
    }

$path here is whatever was passed to the Media constructor, the raw, unvalidated string from mediaDirFunc().

system/config/security.yaml, the Medium sandbox allow-list and the comment directly above it:

    # ...
    # dangerous surface (save, set, copy, deleteFile, toArray, filepath, …) is
    # absent from ALLOWED_ACTIONS and stays blocked.
    - class: 'Grav\Common\Page\Medium\Medium'
      methods: 'url, html, filepath, filename, metadata, srcset, parsedownelement, __tostring, @media_actions'

filepath is named in the comment as something that is supposed to stay blocked, and is then listed as an allowed method one line later.

media_directory in the sandbox's function allow-list:

    - media_directory

Root cause

Two gaps, and the second one converts the first from "list filenames from a directory" into "read the content of files":

1. mediaDirFunc()'s containment check only fires for recognized Grav streams. A plain filesystem path, which is the normal, documented shape of a string, is not a stream by definition, so it always takes the unchecked path.
2. Once a…

Duplicate Advisory

This advisory has been withdrawn because it is a duplicate of GHSA-47ch-6w46-6xm7. This link is maintained to preserve external references.

Original Description

Grav CMS before 2.0.16 contains a path traversal vulnerability in the media_directory() Twig function that fails to validate filesystem paths, allowing authenticated users to enumerate and access files outside intended scope. Attackers with page authoring privileges can supply arbitrary filesystem paths to media_directory() and use the allow-listed filepath accessor on Medium objects to read file contents of any file matching configured media extensions that the web server process can access.