OSEC-2026-23 Multiple issues in Marshal

Several issues have been discovered in the Marshal module: ANT-2026-K7NTK0FT Stale objcounter across unmarshal calls enables null/freed internobjtable indexing ANT-2026-2NJYQWEX Custom block size wraparound in CODECUSTOMLEN allocation ANT-2026-PJC00M7X Unmarshaler accepts forged Closuretag metada...