The Memos application, up to version v0.24.3, allows for the embedding of markdown images with arbitrary URLs. When a user views a memo containing such an image, their browser automatically fetches the image URL without explicit user consent or interaction beyond viewing the memo. This can be exploited by an attacker to disclose the viewing user's IP address, browser User-Agent string, and potentially other request-specific information to the attacker-controlled server, leading to information disclosure and user tracking.
An attacker creates a note (memo) containing an embedded Markdown image pointing to a server controlled by the attacker. When the victim views such a note, their browser automatically sends an HTTP request to the attacker's server to download the image. This request includes the client's IP address and the browser's User-Agent header, and potentially other request metadata. The entire process occurs without any additional user interaction beyond simply opening the note.
An attacker can obtain the victim's IP address, browser identification string (User-Agent), and other information contained in HTTP requests, enabling unauthorized user tracking and profiling of their network environment.
Patches available from the vendor should be applied according to references. Until updates are deployed, it is recommended to restrict note creation by untrusted users or implement a Content Security Policy that blocks loading of external resources.
Usememos Memos up to and including version v0.24.3
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HUsememos Memos
APPUsememos≤ 0.24.3
Related vulnerabilities
SSRF w Usememos Memos — brak walidacji URL dostarczanych przez użytkownika
Improper Access Control in GitHub repository usememos/memos prior to 0.13.2.
Cross-site Scripting (XSS) - Stored in GitHub repository usememos/memos prior to 0.9.1.
Cross-site Scripting (XSS) - Stored in GitHub repository usememos/memos prior to 0.9.1.
Authorization Bypass Through User-Controlled Key in GitHub repository usememos/memos prior to 0.9.0.