alt Hacker NewsThose CVEs seem a little more subtle than OID serialization issues. In the first example there are actually two distinct problems in concert that lead to the vulnerability, one of which is when a "low public exponent" is used.
https://github.com/digitalbazaar/forge/commit/3f0b49a0573ef1...
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maxtaco • yesterday at 11:59 PM
It seems like in that PR, the fact that the OID wasn't checked is part of the problem. I think a better system wouldn't compile or would always fail to verify if the OID (domain separator) is wrong, and I think you'd get that behavior in the posted system.
This is Bleichenbacher's rump-session e=3 RSA attack. It's pretty straightforward, and is in Cryptopals if anyone wants to try it. If you don't check all the RSA padding, and you use e=3, you can just take an integer cube root.