Twig is a template language for PHP. Prior to 3.27.0, ArrayExpression does not guard dynamic mapping keys that are coerced to strings, allowing PHP to invoke __toString() on a Stringable object used as a mapping key without calling SandboxExtension::ensureToStringAllowed(). This issue is fixed in version 3.27.0.
3.20.0-2ubuntu1Exploitability
AV:NAC:LAT:NPR:LUI:NVulnerable System
VC:HVI:LVA:NSubsequent System
SC:NSI:NSA:NCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N