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Ransomware has become a serious threat in the cyberspace. Existing software pattern-based malware detectors are specific for certain ransomware and may not capture new variants. Recognizing a common essential behavior of ransomware - employing local cryptographic software for malicious encryption and therefore leaving footprints on the victim machine's caches, this work proposes an anti-ransomware methodology, Ran$Net, based on hardware activities. It consists of a passive cache monitor to log suspicious cache activities, and a follow-on non-profiled deep learning analysis strategy to retrieve the secret cryptographic key from the timing traces generated by the monitor. We implement the first of its kind tool to combat an open-source ransomware and successfully recover the secret key.
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This content will become publicly available on July 8, 2025
Secure Archival is Hard... Really Hard
Archival systems are often tasked with storing highly valuable data that may be targeted by malicious actors. When the lifetime of the secret data is on the order of decades to centuries, the threat of improved cryptanalysis casts doubt on the long-term security of cryptographic techniques, which rely on hardness assumptions that are hard to prove over archival time scales. This threat makes the design of secure archival systems exceptionally difficult. Some archival systems turn a blind eye to this issue, hoping that current cryptographic techniques will not be broken; others often use techniques--—such as secret sharing—that are impractical at scale. This position paper sheds light on the core challenges behind building practically viable secure long-term archives; we identify promising research avenues towards this goal.
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- PAR ID:
- 10525132
- Publisher / Repository:
- ACM
- Date Published:
- ISBN:
- 9798400706301
- Page Range / eLocation ID:
- 38 to 46
- Subject(s) / Keyword(s):
- Information systems -> Digital libraries and archives Computer systems organization -> Secondary storage organization Security and privacy -> Database and storage security Information-theoretic techniques Archival storage , encryption secret-sharing Harvest Now Decrypt Later information-theoretic security
- Format(s):
- Medium: X
- Location:
- Santa Clara CA USA
- Sponsoring Org:
- National Science Foundation
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