OpenSSL DoS Flaw Lets Unauthenticated Attackers Trigger Massive Memory Allocation

A newly disclosed OpenSSL flaw called "HollowByte" allows an 11-byte malicious TLS ClientHello to trigger unvalidated buffer pre-allocation, causing heavy heap fragmentation and persistent process RSS growth that can lock servers or cause OOM conditions; OpenSSL fixed the issue by switching to incremental buffer growth in v4.0.1 with backports to several 3.x releases, and administrators should urgently update internet-facing TLS endpoints.