CVE-2026-29039: changedetection.io: XPath - Arbitrary File Read via unparsed-text()

changedetection.io is a free open source web page change detection tool. Prior to version 0.54.4, the changedetection.io application allows users to specify XPath expressions as content filters via the include_filters field. These XPath expressions are processed using the elementpath library which implements XPath 3.0/3.1 specification. XPath 3.0 includes the unparsed-text() function which can read arbitrary files from the filesystem. The application does not validate or sanitize XPath expressions to block dangerous functions, allowing an attacker to read any file accessible to the application process. This issue has been patched in version 0.54.4.