CompCap-Stego: Computable Capability-Pointer Steganography with Hidden Policy Evaluation and Verifiable External Payload Retrieval

CompCap-Stego is a capability-pointer steganography frame-work in which the concealed object is a compact dual-zone ca-pability capsule rather than the protected payload. The sealed access zone stores receiver binding, wrapped key material, a revocation handle, an audit nonce, and a payload-verification root, while the computable policy zone supports validity, expiry, bounded-use access, revocation, replay state, receiver matching, honey-state misuse detection, and policy-digest consistency. Here, computable denotes authenticated policy-state evaluation after capsule extraction rather than general-purpose or homo-morphic computation directly over unrecovered steganographic bits. Retrieval proceeds only after capsule extraction, binding validation, policy evaluation, receiver-bound token derivation, and verification of the externally returned encrypted payload. A 512-byte core capsule reduces embedded size by 95.00 percent for a 10-kilobyte (KB) payload, 99.50 percent for 100 KB, 99.95 percent for a 1-megabyte (MB) payload, and 99.995 percent for 10 MB. Carrier quality remains stable at 55.8 to 55.9 decibels (dB) in peak signal-to-noise ratio (PSNR), 0.997 structural simi-larity index measure (SSIM), and 0.56 area under the receiver operating characteristic curve (AUC). Medium error correction reaches 99.6 percent extraction success and 99.5 percent tag-verification success. Policy violations are rejected at 98.9 to 99.8 percent, tampered or replaced external ciphertext at 99.8 to 99.9 percent, and the full design records 0.4 percent compo-site attack success.

@article{Nassar2026,
  title     = {CompCap-Stego: Computable Capability-Pointer Steganography with Hidden Policy Evaluation and Verifiable External Payload Retrieval},
  journal   = {International Journal of Advanced Computer Science and Applications},
  volume    = {17},
  number    = {9},
  year      = {2026},
  publisher = {The Science and Information Organization},
  author    = {Mohammad Othman Nassar},
  doi       = {10.14569/IJACSA.2026.0170928},
  url       = {https://doi.org/10.14569/IJACSA.2026.0170928}
}