hackmdio/codimd

CodiMD through 2.2.0 has a CSP-based protection mechanism against XSS through uploaded JavaScript content, but it can be bypassed by uploading a .html file that references an uploaded .js file.

CodiMD through 2.5.4 has a CSP-based protection mechanism against XSS through uploaded SVG documents containing JavaScript, but it can be bypassed in certain cases of different-origin file storage, such as AWS S3. NOTE: it can be considered a user error if AWS is employed for hosting untrusted JavaScript content, but the selected architecture within AWS does not have components that are able to insert Content-Security-Policy headers.

CodiMD allows realtime collaborative markdown notes on all platforms. CodiMD before 2.5.4 is missing authentication and access control vulnerability allowing an unauthenticated attacker to gain unauthorised access to image data uploaded to CodiMD. CodiMD does not require valid authentication to access uploaded images or to upload new image data. An attacker who can determine an uploaded image's URL can gain unauthorised access to uploaded image data. Due to the insecure random filename generation in the underlying Formidable library, an attacker can determine the filenames for previously uploaded images and the likelihood of this issue being exploited is increased. This vulnerability is fixed in 2.5.4.

CodiMD allows realtime collaborative markdown notes on all platforms. The notebook feature of Hackmd.io permits the rendering of iframe `HTML` tags with an improperly sanitized `name` attribute. This vulnerability enables attackers to perform cross-site scripting (XSS) attacks via DOM clobbering. This vulnerability is fixed in 2.5.4.

HackMD CodiMD <2.5.2 is vulnerable to Denial of Service.

HedgeDoc is open source software which lets you create real-time collaborative markdown notes. In HedgeDoc before version 1.7.2, an attacker can inject arbitrary JavaScript into a HedgeDoc note, which is executed when the note is viewed in slide mode. Depending on the configuration of the instance, the attacker may not need authentication to create or edit notes. The problem is patched in HedgeDoc 1.7.2. As a workaround, disallow loading JavaScript from 3rd party sites using the `Content-Security-Policy` header. Note that this will break some embedded content.

HedgeDoc is a collaborative platform for writing and sharing markdown. In HedgeDoc before version 1.7.1 an attacker can inject arbitrary `script` tags in HedgeDoc notes using mermaid diagrams. Our content security policy prevents loading scripts from most locations, but `www.google-analytics.com` is allowed. Using Google Tag Manger it is possible to inject arbitrary JavaScript and execute it on page load. Depending on the configuration of the instance, the attacker may not need authentication to create or edit notes. The problem is patched in HedgeDoc 1.7.1. As a workaround one can disallow `www.google-analytics.com` in the `Content-Security-Policy` header. Note that other ways to leverage the `script` tag injection might exist.

CodiMD 1.3.1, when Safari is used, allows XSS via an IFRAME element with allow-top-navigation in the sandbox attribute, in conjunction with a data: URL.