Service hang via incorrect parser EOF handling

Improper input validation in Amazon.IonDotnet before 1.3.2 allows remote attackers to hang consuming applications via crafted Ion text. The TextScanner parser compares end-of-file results against the wrong sentinel and omits EOF checks while scanning blobs and quoted strings, so malformed or unterminated data remains in parser loops instead of terminating. Exploitation requires an application to parse attacker-controlled text; the resulting infinite loop consumes processing capacity and interrupts that application's service.