Unchecked Access (unsafe pointers): http://www.ada-auth.org/standards/22rm/html/RM-13-10.html#I5...

Unchecked Deallocations ("free"): http://www.ada-auth.org/standards/22rm/html/RM-13-11-2.html#...

Unchecked type conversions (unsafe casting): http://www.ada-auth.org/standards/22rm/html/RM-13-9.html#I57...

Ada has FFI:

C / C++: http://www.ada-auth.org/standards/22rm/html/RM-B-3.html

COBOL: http://www.ada-auth.org/standards/22rm/html/RM-B-4.html

Fortran: http://www.ada-auth.org/standards/22rm/html/RM-B-5.html

Ada has pragmas to both enable more security measures or relax security measures:

http://www.ada-auth.org/standards/22rm/html/RM-L.html

Just like in unsafe Rust, sometimes in Ada you need to turn off some security features or tell the compiler "I know what I am doing for this part" when interfacing with some hardware or similar low-level stuff.