RFC 2040, "The RC5, RC5-CBC, RC5-CBC-Pad, and RC5-CTS Algorithms", October 1996

Errata ID: 514
Status: Verified
Type: Technical
Publication Format(s) : TEXT
Reported By: Bob Baldwin
Date Reported: 2004-03-26

Section 8 says:

   1. Exclusive-or Pn-1 with the previous ciphertext
      block, Cn-2, to create Xn-1.

It should say:

   1. Exclusive-or Pn-1 with the previous ciphertext
      block, Cn-2, to create Xn-1.  For short messages where
      Cn-2 does not exist, use IV.

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