Twig is a template language for PHP. Prior to 3.26.0, the deprecated spaceless filter is registered as safe for HTML, causing Twig autoescaping to emit attacker-controlled markup unescaped when spaceless is applied to untrusted input. This issue is fixed in version 3.26.0.
Exploitability
AV:NAC:LAT:NPR:LUI:PVulnerable System
VC:NVI:NVA:NSubsequent System
SC:LSI:LSA:N5.1/CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:NInput Validation