Security researchers at VUSec disclosed Branch Target Reuse (BTR), a Spectre-V2 attack targeting JIT compilers in the Linux kernel's BPF, Oracle GraalVM, and Mozilla Firefox's SpiderMonkey engine. BTR exploits stale indirect branch prediction entries to leak arbitrary memory, affecting Intel, AMD, and Arm processors. Mitigations including IBPB flushing and JIT code randomization have been deployed across affected platforms.