Introducing the H3 Collective PE Cert Mutator Tool
The H3 Collective is releasing an alpha version of a PE cert fuzzing tool. We use this internally (among other tools) to test some of our software products and wanted to let others leverage it for their use. Rolling out your own ASN.1 parsing and certificate validation tools can be tricky at best, potentially introducing very serious security bugs if they have not been thoroughly tested. Sometimes leveraging an existing fuzzing framework isn’t possible because of how the software is built or what platform it runs on. This tool takes an existing binary and mutates components related to the authenticode signature. Currently it can mutate the security data directory, the WIN_CERTIFICATE struct inside of the attribute certificate table, and bCertificate field. You can use it to swap in the signature from another signed binary before mutations are made, in case you have a valid binary from which you’d like to leverage the signature…