Multiple cross-site request forgery (CSRF) vulnerabilities in Koha 3.14.x before 3.14.16, 3.16.x before 3.16.12, 3.18.x before 3.18.08, and 3.20.x before 3.20.1 allow remote attackers to (1) hijack the authentication of administrators for requests that create a user via a request to members/memberentry.pl or (2) give a user superlibrarian permission via a request to members/member-flags.pl or (3) hijack the authentication of arbitrary users for requests that conduct cross-site scripting (XSS) attacks via the addshelf parameter to opac-shelves.pl.

Multiple cross-site scripting (XSS) vulnerabilities in Koha 3.14.x before 3.14.16, 3.16.x before 3.16.12, 3.18.x before 3.18.08, and 3.20.x before 3.20.1 allow remote attackers to inject arbitrary web script or HTML via the (1) tag parameter to opac-search.pl; the (2) value parameter to authorities/authorities-home.pl; the (3) delay parameter to acqui/lateorders.pl; the (4) authtypecode or (5) tagfield to admin/authsubfieldsstructure.pl; the (6) tagfield parameter to admin/marcsubfieldsstructure.pl; the (7) limit parameter to catalogue/search.pl; the (8) booksellerfilter, (9) callnumberfilter, (10) EANfilter, (11) ISSNfilter, (12) publisherfilter, or (13) titlefilter parameter to serials/serials-search.pl; or the (14) author, (15) collectiontitle, (16) copyrightdate, (17) isbn, (18) manageddatefrom, (19) manageddateto, (20) publishercode, (21) suggesteddatefrom, or (22) suggesteddateto parameter to suggestion/suggestion.pl; or the (23) direction, (24) display or (25) addshelf parameter to opac-shelves.pl.

Multiple cross-site scripting (XSS) vulnerabilities in the Staff client in Koha before 3.16.6 and 3.18.x before 3.18.2 allow remote attackers to inject arbitrary web script or HTML via the sortby parameter to the (1) opac parameter in opac-search.pl or (2) intranet parameter in catalogue/search.pl.