Part-DB is an open source inventory management system for electronic components. Prior to version 2.12.1, LogEntryExtraFormatter builds the HTML shown in the "Extra" column of the activity-log table (/log) and in element history tables. Every branch of LogEntryExtraFormatter::getInternalFormat() runs user-controlled strings through htmlspecialchars() before placing them into the HTML it returns β except the CollectionElementDeleted branch, which interpolates getOldName() (and getCollectionName()) into a sprintf() template with no escaping. The returned string is emitted by LogEntryExtraColumn::render() and inserted as raw HTML into the DataTables cell (the bundle does not escape column output; sibling columns call htmlspecialchars() themselves). CollectionElementDeleted.getOldName() is the name of a deleted collection sub-element β a part Parameter, Attachment, PartLot, Orderdetail, etc. β all freely set by any user with edit rights on the owning element. A low-privileged content editor can therefore store an HTML/script payload as the name of such a sub-element, delete it (which writes the log entry), and have that markup parsed as live DOM in the browser of a higher-privileged victim (an administrator/auditor with system.show_logs, or any user viewing that element's history). This is a stored cross-site-scripting / HTML-injection defect caused by a single missed sanitizer in one sibling branch. CSP policies block inline javascript execution under normal conditions. This isβ¦