Shaarli is a personal bookmarking service. Versions 0.16.1 and prior contain a DOM-based Cross-Site Scripting (XSS) vulnerability in the Thumbnail Synchronizer feature. When an administrator runs the thumbnail update process, malicious bookmark titles are returned via an AJAX response and inserted into the DOM using innerHTML without proper sanitization. The issue originates from the interaction between the backend thumbnail update endpoint and the frontend JavaScript responsible for rendering update progress. On the backend, the ThumbnailsController::ajaxUpdate method returns bookmark data formatted using the 'raw' formatter. This includes the unescaped bookmark title in the JSON response. On the client side, the script thumbnails-update.js processes this AJAX response and dynamically updates the progress interface. Administrators using the thumbnail synchronization feature are affected and exploitation could lead to session hijacking, privilege escalation, backdoor injection and full compromise. This issue has been fixed in version 0.16.2.
History

Thu, 18 Jun 2026 16:45:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Thu, 18 Jun 2026 04:45:00 +0000

Type Values Removed Values Added
Description Shaarli is a personal bookmarking service. Versions 0.16.1 and prior contain a DOM-based Cross-Site Scripting (XSS) vulnerability in the Thumbnail Synchronizer feature. When an administrator runs the thumbnail update process, malicious bookmark titles are returned via an AJAX response and inserted into the DOM using innerHTML without proper sanitization. The issue originates from the interaction between the backend thumbnail update endpoint and the frontend JavaScript responsible for rendering update progress. On the backend, the ThumbnailsController::ajaxUpdate method returns bookmark data formatted using the 'raw' formatter. This includes the unescaped bookmark title in the JSON response. On the client side, the script thumbnails-update.js processes this AJAX response and dynamically updates the progress interface. Administrators using the thumbnail synchronization feature are affected and exploitation could lead to session hijacking, privilege escalation, backdoor injection and full compromise. This issue has been fixed in version 0.16.2.
Title Shaarli: DOM-based Cross-Site Scripting (XSS) in Thumbnail Synchronizer
Weaknesses CWE-79
References
Metrics cvssV3_1

{'score': 5.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:H/UI:R/S:U/C:H/I:H/A:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-06-18T12:57:01.649Z

Reserved: 2026-05-22T20:57:10.977Z

Link: CVE-2026-48821

cve-icon Vulnrichment

Updated: 2026-06-18T12:56:51.860Z

cve-icon NVD

No data.

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.