CVE-2026-44608 NLnet Labs Unbound 锁定不一致漏洞

import threading import time # Conceptual simulation of the race condition # This is a simplified representation of the locking logic issue. class RPZZone: def __init__(self): self.data = [1, 2, 3, 4, 5] self.lock = threading.Lock() def read_zone(self): # Simulating the reader thread not holding the lock long enough print("Reader: Trying to read...") # In the vulnerable version, the lock might be released too early with self.lock: time.sleep(0.001) # Simulate context switch # self.data might be freed here by another thread for item in self.data: print(f"Reader item: {item}") def xfr_reload(self): # Simulating the XFR thread freeing objects print("XFR: Reloading zone...") with self.lock: print("XFR: Freeing old data...") self.data = [] # Freeing the list zone = RPZZone() # Simulate concurrent access t1 = threading.Thread(target=zone.read_zone) t2 = threading.Thread(target=zone.xfr_reload) t1.start() t2.start() t1.join() t2.join() print("Potential crash if reader accesses freed data.")