I Found a $113,337 Af_alg Linux Local Privilege Escalation Before Copy Fail

Muhammad Alifa Ramdhan discovered CVE-2025-39964, a Linux kernel AF_ALG vulnerability enabling unprivileged users to escalate to root through a race condition between socket writers. The flaw, present since 2011, was responsibly disclosed and earned a $113,337 Google kernelCTF reward; it differs from the later Copy Fail vulnerability and can also escape Docker containers.