10

Looking at the code of the iota.lib.js' bundle creation mechanism, a normalized hash is computed and then checked for inclusion of 13 /* = M */. If one is found, the obsoleteTag is incremented, and the hashing is repeated.

What is the reason behind a 13 indicating an insecure bundle hash?

2
  • 3
    When the normalized hash contains a 'M', the signing process will leave that block of the private key unhashed. If there was a bug in generating the private key that allowed correlations from a leaked block to future blocks, it would cause more than that one block to leak. The IOTA foundation promised a blog post about the backgrounds when they (turned off the coo for 3 days and) fixed that bug, but so far nothing was released, so I guess any answers to that question which do not come from the core team would be speculation.
    – mihi
    Commented Jan 12, 2018 at 19:25
  • I’m voting to close this question because it is about the legacy-network and it is a good idea to keep only Shimmer/ShimmerEVM and latest IOTA Chrysalis questions Commented Apr 24, 2023 at 14:05

1 Answer 1

9

There was a bug in the wallet software related to absence of https://github.com/Come-from-Beyond/ISS/commit/de1a279450558848a81858fd57b023719eb9a0d3. "M" should be avoided to prevent leakage of the corresponding (and following) private key fragments.

4
  • And to clarify, do I understand this change correctly that implementing this change would change the key generation algorithm so everybody would have to transition again; therefore the IOTA foundation decided to "paper over" this bug instead of fixing by preventing 'M' in normalized hash?
    – mihi
    Commented Jan 13, 2018 at 12:58
  • Address generation algorithm would indeed be changed, for the IOTA Foundation's choice you should ask them. Commented Jan 13, 2018 at 13:08
  • 2
    What is your affiliation to the Foundation? I did ask them (shortly after the incident) and they said that they will make a blog post about this issue (describing both why it is insecure and why they decided to fix it as they did) available later. Not happened yet and being polite I don't ask again...
    – mihi
    Commented Jan 13, 2018 at 14:08
  • I code stuff which the Foundation uses in their projects. Commented Jan 13, 2018 at 15:54

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.