NULL Pointer Dereference in GnuTLS Affects Nettle's Hash Update Functions

CVE-2021-4209

Summary

A NULL pointer dereference flaw exists in GnuTLS, impacting its hash update functions within Nettle. This vulnerability arises when zero-length input is provided, leading to potential undefined behavior. In some rare scenarios, this may result in a denial of service occurring after user authentication.

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