vbpf prevail

• CVE-2026-53706 High 8.8 PREVAIL: ALU32 pointer arithmetic accepted without is64 gate — verifier emits false PASS for pointer-corrupting programs 0.5%
• CVE-2026-53670 Critical 9.3 PREVAIL: Non-singleton typeset in add() skips offset update, allowing OOB access to pass eBPF verification 0.5%
• CVE-2026-53671 Critical 9.3 PREVAIL: Context-write no-op in do_mem_store allows unsafe eBPF programs to pass verification 0.5%