Title
Validating the Integrity of Audit Logs Against Execution Repartitioning Attacks
Abstract
ABSTRACTProvenance-based causal analysis of audit logs has proven to be an invaluable method of investigating system intrusions. However, it also suffers from dependency explosion, whereby long-running processes accumulate many dependencies that are hard to unravel. Execution unit partitioning addresses this by segmenting dependencies into units of work, such as isolating the events that processed a single HTTP request. Unfortunately, we discover that current designs have a semantic gap problem due to how system calls and application log messages are used to infer complex internal program states. We demonstrate how attackers can modify existing code exploits to control event partitioning, breaking links in the attack and framing innocent users. We also show how our techniques circumvent existing program and log integrity defenses. We then propose a new design for execution unit partitioning that leverages additional runtime data to yield verified partitions that resist manipulation. Our design overcomes the technical challenges of minimizing additional overhead while accurately connecting low level code instructions to high level audit events, in part with the use of commodity hardware processor tracing. We implement a prototype of our design for Linux, MARSARA, and extensively evaluate it on 14 real-world programs, targeted with expertly crafted exploits. MARSARA's verified partitions successfully capture all the attack provenances while only reintroducing 2.82% of false dependencies, in the worst case, with an average overhead of 8.7%. Using a new metric called Partitioning Attack Surface, we show that MARSARA eliminates 47,642 more repartitioning gadgets per program than integrity defenses like CFI, demonstrating our prototype's effectiveness and the novelty of the attacks it prevents.
Year
DOI
Venue
2021
10.1145/3460120.3484551
Computer and Communications Security
Keywords
DocType
Citations 
auditing, execution unit partitioning, processor tracing
Conference
1
PageRank 
References 
Authors
0.35
0
6
Name
Order
Citations
PageRank
Carter Yagemann172.79
Mohammad A. Noureddine210.35
Wajih Ul Hassan3547.07
Aloysius K. Mok4797.92
Adam Bates532423.66
Wenke Lee69351628.83