NIST opens comments on draft SP 800-38Er1 updating XTS-AES guidance

What happened

• NIST has issued a draft revision of Special Publication 800‑38Er1, which endorses XTS‑AES for storage encryption and aligns the recommendation with IEEE Std 1619‑2025.
• The draft clarifies usage scope, data‑unit limits, key requirements and ciphertext‑stealing order.
• A public comment period runs until 16 October 2026, and the draft includes a call for patent claims.
• The document is available on the NIST website for review.

Why it matters

Entities that rely on XTS‑AES for encrypting data at rest should verify that their implementations meet the newly defined key‑scope and data‑unit limits before the final standard is issued.

Business impact

Non‑compliant encryption configurations may need redesign or re‑keying, affecting product roadmaps and security‑as‑a‑service offerings.

What to check

1. 1

   Review draft SP 800‑38Er1High priority

   Compare current XTS‑AES implementations against the updated data‑unit and key‑scope limits.

2. 2

   Submit comments to NISTMedium priority

   Provide feedback on technical or patent‑related concerns before 16 October 2026.

3. 3

   Assess patent exposureMedium priority

   Determine whether any patented technology in your XTS‑AES solution may be affected by the draft’s patent‑claim call.