CVE-2026-81731 in Frappe
Summary
by MITRE • 08/27/2026
Frappe 15.11.0 through 16.32.0 stores and renders the workspace card description without XSS filtering. The description field of the Workspace Link doctype is declared with "ignore_xss_filter": 1 in frappe/desk/doctype/workspace_link/workspace_link.json, and _sanitize_content() in frappe/model/base_document.py skips any field carrying that flag, so the value is stored exactly as submitted. frappe.desk.desktop.get_desktop_page returns it unchanged, and LinksWidget.set_body() in frappe/public/js/frappe/widgets/links_widget.js interpolates it into a Bootstrap popover created with html: true, by way of the __() translation helper, which performs no HTML escaping. A user holding the Workspace Manager role can therefore place arbitrary markup in a public workspace's card description and have it execute in the session of any desk user who opens that workspace and hovers the description, including higher-privileged users, allowing session token theft and authenticated requests as the victim. The flag is removed on the development branch but remains present in the shipped 15.x and 16.x release lines, so no released version carries the fix.
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Analysis
by VulDB Data Team • 08/27/2026
The vulnerability identified involves a stored cross-site scripting flaw within Frappe versions 15.11.0 through 16.32.0, specifically affecting the workspace card description functionality. This security issue stems from an intentional configuration choice where the description field of the Workspace Link doctype is marked with ignore_xss_filter set to one in the system's JSON definition files. Consequently, when data is processed by the base document sanitization logic, any content associated with this flag bypasses standard HTML escaping and filtering mechanisms. The application stores these inputs exactly as submitted without modification, preserving potentially malicious scripts or markup that were originally injected into the field.
The exploitation of this vulnerability occurs during the rendering phase within the user interface layer. When a desk user navigates to a workspace containing an affected card description, the system retrieves the raw content via specific desktop page retrieval functions. This unescaped data is then passed through translation helpers and interpolated directly into Bootstrap popovers configured with HTML enabled for display purposes. Because no additional escaping occurs at this stage of rendering, any script tags or event handlers embedded in the stored description are executed immediately upon interaction by the victim user.
The operational impact of this flaw allows an attacker holding the Workspace Manager role to inject arbitrary client-side code into public workspaces accessible to other users. By crafting a malicious payload within the card description field, the attacker can trigger execution when any desk user hovers over or interacts with the affected workspace card. This interaction leads to session token theft and enables authenticated requests performed under the context of higher-privileged victims. The attack effectively bypasses role-based access controls by leveraging trusted application functionality to execute code in the security context of privileged users, facilitating potential full account compromise.
Industry standards classify this vulnerability as a classic example of stored cross-site scripting where input validation is explicitly disabled for specific fields without compensating controls at output time. It aligns with CWE-79 Improper Neutralization of Input During Web Page Generation and reflects techniques documented in the MITRE ATT&CK framework under client-side injection patterns. The persistence of this flaw across multiple major release lines indicates a systemic design oversight where security flags are retained despite known risks, requiring immediate attention from development teams to align with secure coding practices that mandate strict output encoding regardless of input filtering settings.
Mitigation strategies must address both the configuration and rendering layers of the application. Administrators should immediately restrict Workspace Manager privileges to trusted individuals while awaiting a patch. Developers need to remove the ignore_xss_filter flag for sensitive fields or implement robust output encoding mechanisms such as context-aware HTML escaping before data is interpolated into DOM elements. Additionally, implementing Content Security Policy headers can help mitigate the impact of any remaining script execution by restricting source origins and preventing inline script evaluation unless explicitly whitelisted. Regular security audits focusing on doctype configurations are essential to prevent similar oversights in future releases.