YesWiki is a wiki system written in PHP. The squelette parameter is vulnerable to path traversal attacks, enabling read access to arbitrary files on the server. This vulnerability is fixed in 4.5.2.
https://github.com/YesWiki/yeswiki/security/advisories/GHSA-w34w-fvp3-68xm
https://github.com/YesWiki/yeswiki/commit/f78c915369a60c74ab8f38561ae93a4aaca9b989