CVE 2021-39213
GLPI is a free Asset and IT management software package. Starting in version 9.1 and prior to version 9.5.6, GLPI with API Rest enabled is vulnerable to API bypass with custom header injection. This issue is fixed in version 9.5.6. One may disable API Rest as a workaround.
See the
CVE page on Mitre.org
for more details.