RFC 5054, "Using the Secure Remote Password (SRP) Protocol for TLS Authentication", November 2007

Errata ID: 4546
Status: Reported
Type: Technical
Publication Format(s) : TEXT
Reported By: Rick van Rein
Date Reported: 2015-11-30

Section 2.6 says:

B = k*v + g^b % N

It should say:

B = ( k*v + g^b ) % N

Notes:

The customary binding is that + has lower priority than % and so the default reading of the expression would be
B = k*v + ( g^b % N )
That is inconsistent with the existence of PAD(B) and the size of B in the test vectors, so the context hints at proper brackets, but this may still lead to implementation errors (of which I actually ran into an example).

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