The psqlODBC parser for ODBC escape sequences in application SQL text writes the argument offsets of a {fn} escape into…

The psqlODBC parser for ODBC escape sequences in application SQL text writes the argument offsets of a {fn} escape into a fixed 16-entry stack array without a bound and does not initialize the array. An escape with too many arguments overflows the stack, and a reference to an unsupplied argument copies arbitrary bytes into the query. The copy of a {d}, {t}, {ts}, or {escape} body also writes one byte past a 128-byte stack buffer. An application that forwards untrusted SQL text to the driver exposes its process to memory corruption. Versions before psqlODBC 18.00.0006 are affected.