Grav before 2.0.20 Cross-Site Scripting via Assets Sandbox
Grav before 2.0.20 contains a cross-site scripting vulnerability in the Twig sandbox policy that allowlists addJs and addCss methods on Grav\Common\Assets without proper output escaping. Page editors can inject arbitrary script by registering malicious assets or injecting attributes, which are rendered unescaped into document head tags and executed for all visitors including administrators.
Grav before 2.0.16 Information Disclosure via Twig Sandbox
Grav before 2.0.16 contains an incomplete default denylist in the Twig sandbox configuration that fails to block access to system configuration secrets. Attackers with page-edit permission can use config.get() or config.toArray() in Twig templates to retrieve sensitive values like system.cache.redis.password when config_access is enabled.
Grav before 2.0.16 Information Disclosure via offsetGet
Grav before 2.0.16 allows sandboxed Twig templates to access sensitive User fields through allow-listed offsetGet() and offsetexists() methods that lack field filtering. Attackers with page-edit permissions can call offsetGet() on User objects to extract hashed passwords and 2FA secrets, enabling offline password cracking and authentication bypass.
Grav CMS before 2.0.16 Origin Validation Bypass via Referer
Grav CMS before 2.0.16 contains an origin validation bypass in the Uri::referrer() and Pages::referrerRoute() methods, which validate the Referer header using an unanchored string prefix match (str_starts_with($referrer, $base)) with no trailing delimiter. An attacker who controls a domain that begins with the victim site's origin (e.g. https://example.com.attacker.tld) can send a request with such a Referer to be treated as same-origin, bypassing the Referer-based origin check.
Grav CMS before 2.0.16 Timing Attack via verifyNonce
Grav CMS before 2.0.16 contains a timing vulnerability in Utils::verifyNonce() that uses non-constant-time string comparison with the === operator instead of hash_equals() for CSRF nonce validation. Attackers can measure response timing differences to recover valid nonce values byte-by-byte through multiple requests, weakening CSRF protection below its intended security margin.
Grav CMS before 2.0.16 Information Disclosure via Twig Sandbox Bypass
Grav CMS before 2.0.16 fails to filter system, site, and theme configuration arrays in sandboxed Twig renders, allowing content editors to read sensitive configuration values. Attackers with page-content edit access can access raw configuration arrays including secrets like cache credentials by using dot notation in Twig templates, bypassing the config_denied_paths restrictions.
Grav CMS before 2.0.16 Path Traversal via media_directory
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 before 2.0.16 Path Traversal via MediaUploadTrait deleteFile
Grav before 2.0.16 contains a path traversal vulnerability in MediaUploadTrait::deleteFile() that allows authenticated users with media management permissions to delete arbitrary files by supplying filenames with directory traversal sequences. The method validates only the basename portion of the filename while preserving unvalidated directory paths containing ../ sequences that are passed to unlink(), enabling deletion of files outside the intended media storage directory.
Grav: Remote code execution via unrestricted callable in Blueprint::dynamicData()
Grav is a file-based Web platform. Prior to 2.0.7, Grav Blueprint::dynamicData() in system/src/Grav/Common/Data/Blueprint.php sends an editor-controlled Class::method provider and arguments to call_user_func_array() without rejecting dangerous callback parameters. An account with admin.pages or api.pages.write can use Grav\Common\Utils::arrayFilterRecursive() as a trampoline with system as the callback, place a command in page frontmatter, and execute that command as the web server user when the page is viewed. This issue is fixed in version 2.0.7.
Grav before 2.0.14 Privilege Escalation via Group Access Field
Grav before 2.0.14 fails to guard the access field in the core group blueprint with the required security@: admin.super restriction. A delegated admin.users operator can save a group with access[admin][super]=true to escalate to super-admin, gaining scheduler and Twig evaluation capabilities.
Grav before 2.0.14 Stored XSS via Invalid UTF-8 Byte
Grav before 2.0.14 contains a stored cross-site scripting vulnerability in the Security::detectXss() function (system/src/Grav/Common/Security.php). All XSS detection patterns use the PCRE /u (UTF-8) modifier, so a single invalid UTF-8 byte anywhere in page content causes preg_match() to return false for every pattern, silently bypassing the save-time XSS safety gate (Validation::checkSafety()). An authenticated attacker with page-edit permissions (without the security.xss_whitelist privilege) can store malicious JavaScript that executes in the browser of a visitor who views the affected page.
Grav before 2.0.15 Stored XSS via audio/video source URL
Grav before 2.0.15 contains a stored cross-site scripting vulnerability in the audio and video media rendering through the sourceParsedownElement method. The media URL fragment is concatenated unescaped into rawHtml source elements, allowing attackers to inject arbitrary HTML and JavaScript that executes in viewers' sessions.
Grav before 2.0.15 Stored XSS via detectXss() Quote Bypass
Grav before 2.0.15 contains a stored cross-site scripting vulnerability in the detectXss() function where unpaired quotes in unquoted attribute values bypass event-handler detection. Authenticated editors can inject event handlers like onerror= that pass validation and execute in visitor browsers when page content is rendered.
Grav before 2.0.15 Arbitrary File Write via error_log
Grav before 2.0.15 contains an arbitrary file write vulnerability in the Blueprint dynamic-data bare-function validation that uses an incomplete denylist instead of a positive allowlist. Attackers with page-edit or blueprint-config access can invoke the error_log function through a data directive to append PHP payloads to web-accessible files, achieving remote code execution.
Grav before 2.0.15 Path Traversal via plugin-asset-map.php
Grav before 2.0.15 contains a path traversal vulnerability in the static asset server within index.php that uses string prefix matching instead of directory-boundary validation. Unauthenticated attackers can access files in sibling directories by exploiting directory names that extend the base path string, such as requesting assets-secret when assets is the configured base.
Grav before 2.0.12 Stored XSS via quoted-attribute bypass
Grav versions from 1.5.2 through 2.0.12 contain a stored cross-site scripting vulnerability in the Security::detectXss() function (system/src/Grav/Common/Security.php). The event-handler scan is anchored at `<` and uses `[^>]*?`, which cannot cross the first literal `>`; when a `>` appears inside a quoted attribute value the browser keeps the tag open and parses a subsequent event handler (e.g. onerror), so the detector and browser disagree. A page editor without admin.super privileges can save page content such as `<img src=x title=">" onerror=alert(document.domain)>`, which is accepted, stored, and executed in the site origin when any visit
Grav CMS before 2.0.13 Remote Code Execution via ZIP Upload
Grav CMS before 2.0.13 contains a remote code execution vulnerability in the Flex Objects plugin settings validation that allows authenticated users to execute arbitrary code by uploading a ZIP file containing PHP code. Attackers can bypass routine name validation by using array notation instead of string notation, call the unZip routine with a malicious archive, and write PHP files to the web root for execution.
Grav CMS before 2.0.11 Path Traversal via watermark
Grav CMS 2.0.10 contains a path traversal vulnerability in ImageMedium::watermark(), which passes its unsanitized $image argument to RocketTheme\Toolbox\ResourceLocator\UniformResourceLocator::findResource(). Because the file:// scheme branch only lexically collapses '..' segments without a realpath/containment check, an editor authoring Markdown image syntax with traversal sequences can cause arbitrary image files outside Grav's media sandbox to be composited into a carrier image, which is then cached and served from a public, unauthenticated URL — disclosing those files to anonymous visitors.
Grav CMS 2.0.7 through 2.0.10 Arbitrary Method Invocation via Blueprint
Grav CMS versions 2.0.7 through 2.0.10 fail to validate fully-qualified static method calls (Class::method) in blueprint dynamic-field directives because Blueprint::isSafeDynamicCall() only applies its dangerous-callable denylist to strings that do not contain '::'. An account with only page-editing rights (admin.pages, not super-admin or admin.pages_twig) can plant a directive in a page's form-field frontmatter that invokes an arbitrary public static PHP method with attacker-controlled arguments. Using built-in gadget methods this allows reading of any server-readable file (disclosed to anonymous visitors of the crafted page) and arbitrary c
Grav before 2.0.9 Remote Code Execution via FlexDirectory
Grav versions >= 1.7.0 and before 2.0.9 contain a remote code execution vulnerability. FlexDirectory::dynamicDataField() resolves blueprint data-*@: directives by calling call_user_func_array() on attacker-influenced input, validating only that the target is callable (is_callable()) without restricting dangerous functions such as exec, system, passthru, or shell_exec. Because FlexDirectory registers this handler for every Flex directory, it bypasses the validation added to Blueprint::dynamicData() in 2.0.7 (GHSA-fj2p-qj2f-74v5). Any authenticated user with create or update permission on any Flex-based directory (Flex Users, Flex Pages, Flex O