Microsoft has reminded customers that multiple .NET Framework versions signed using the insecure Secure Hash Algorithm 1 (SHA-1) will reach their end of life this month. The .NET Framework is a free ...
Update May 2018. As many noted in the comments that using SHA-2 does not add any security to a self-signed certificate. But I still recommend using it as a good habit of not using outdated / insecure cryptographic hash functions. Full explanation is available in Why is it fine for certificates above the end-entity certificate to be SHA-1 based?.
Security researchers have achieved the first real-world collision attack against the SHA-1 hash function, producing two different PDF files with the same SHA-1 signature. This shows that the algorithm ...