human: Given a hyperedge-centered hypergraph: <hypergraph>, where the center hyperedge is induced by one source paper and its member nodes are the cited papers.

Details of the hypergraph:
Center hyperedge (induced by source paper "data exfiltration via multipurpose rfid cards and countermeasures"):
  Abstract: Radio-frequency identification(RFID) technology is widely applied in daily human life. The RFID cards are seen everywhere, from entrance guard to consumption. The information security of RFID cards, such as data confidentiality, tag anonymity, mutual authentication etc, has been fully studied. In the paper, using the RFID cards in MIFARE Classic and DESFire families, a bidirectional covert channel via multipurpose RFID cards between service providers is built to leak sensitive data between two simulation systems. Furthermore, by calculations and experiments, the daily channel capacity to leak data of the channel is obtained. Although the storage capacity of a single RFID card is very small, a large user base can still bring about a considerable amount to leak data. Then, the reasons for the existence of such channels are discussed. To eliminate this type of covert channels, a new authentication protocol between RFID cards and card readers are proposed. Our experimental results show a significant security improvement in prevention of such covert communications while keeping user convenience.

Includes members:
  Member "optical exfiltration of data via keyboard led status indicators to ip cameras":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "powerhammer exfiltrating data from air gapped computers through power lines")
  Member "spectre attacks exploiting speculative execution":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "towards probabilistic verification of machine unlearning")
  Member "xled covert data exfiltration from air gapped networks via router leds":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "oops had the silly thing in reverse optical injection attacks in through led status indicators")
  Member "usbee air gap covert channel via electromagnetic emission from usb":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "oops had the silly thing in reverse optical injection attacks in through led status indicators")
  Member "fansmitter acoustic data exfiltration from speakerless air gapped computers":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "your noise my signal exploiting switching noise for stealthy data exfiltration from desktop computers")
  Member "on covert acoustical mesh networks in air":
    also connected through other hyperedges:
      - Hyperedge HE-6 (induced by source paper "your noise my signal exploiting switching noise for stealthy data exfiltration from desktop computers")
  Member "airhopper bridging the air gap between isolated networks and mobile phones using radio frequencies":
    also connected through other hyperedges:
      - Hyperedge HE-7 (induced by source paper "brightness leaking sensitive data from air gapped workstations via screen brightness")

Question: Please tell me which class the source paper belongs to. The 40 classes are: cs.NA(Numerical Analysis), cs.MM(Multimedia), cs.LO(Logic in Computer Science), cs.CY(Computers and Society), cs.CR(Cryptography and Security), cs.DC(Distributed, Parallel, and Cluster Computing), cs.HC(Human-Computer Interaction), cs.CE(Computational Engineering, Finance, and Science), cs.NI(Networking and Internet Architecture), cs.CC(Computational Complexity), cs.AI(Artificial Intelligence), cs.MA(Multiagent Systems), cs.GL(General Literature), cs.NE(Neural and Evolutionary Computing), cs.SC(Symbolic Computation), cs.AR(Hardware Architecture), cs.CV(Computer Vision and Pattern Recognition), cs.GR(Graphics), cs.ET(Emerging Technologies), cs.SY(Systems and Control), cs.CG(Computational Geometry), cs.OH(Other Computer Science), cs.PL(Programming Languages), cs.SE(Software Engineering), cs.LG(Machine Learning), cs.SD(Sound), cs.SI(Social and Information Networks), cs.RO(Robotics), cs.IT(Information Theory), cs.PF(Performance), cs.CL(Computation and Language), cs.IR(Information Retrieval), cs.MS(Mathematical Software), cs.FL(Formal Languages and Automata Theory), cs.DS(Data Structures and Algorithms), cs.OS(Operating Systems), cs.GT(Computer Science and Game Theory), cs.DB(Databases), cs.DL(Digital Libraries), cs.DM(Discrete Mathematics). Directly output the class name.

gpt: cs.CR(Cryptography and Security)