The Inevitability of Failure: The Flawed Assumption of Security in Modern Computing Environments presented by Toby

Introduction

Introduction Premise 1.Ppl be debating lots of security additions without much talk about the operating systems

Introduction Premise 1.Ppl be debating lots of security additions without much talk about the operating systems 2.Debates are flawed—assume that application level security can be attained on current operating systems

Introduction Premise 1.Ppl be debating lots of security additions without much talk about the operating systems 2.Debates are flawed—assume that application level security can be attained on current operating systems 3.Current (err.. 15 year old) operating systems are inadequate from a security standpoint

2 The Missing Link

Mandatory Security Trusted Path

2 The Missing Link Mandatory Security Mandatory Security: “...any security policy where the definition of the policy logic and the assignment of security attributes is tightly controlled by a system security policy administrator.” –this paper The user should have no influence over the security policy in theory

2 The Missing Link Mandatory Security Example systems that should have Mandatory Security: access control authentication usage cryptographic usage

2 The Missing Link Mandatory Security According to the big black box, Mandatory Security has these general benefits: Confinement of applications (from a security standpoint) Lack of burden on individual users to manage security Narrowing of bandwidth of channels for leaking private information Increased accountability of unauthorized private information flow

2 The Missing Link Mandatory Security Example of 1998 state of OSes Windows NT: Two security domains: Complete Privilege Complete Unprivileged Pretty coarse-grained

2 The Missing Link Trusted Path “A trusted path is a mechanism by which a user may directly interact with trusted software, which can only be activated by either the user or the trusted software and may not be imitated by other software.” –this paper

2 The Missing Link Trusted Path “A trusted path is a mechanism by which a user may directly interact with trusted software, which can only be activated by either the user or the trusted software and may not be imitated by other software.” –this paper

2 The Missing Link Trusted Path Example given: Windows NT: Trusted path given for stuff like password changing But no means for extending to other trusted software

3 General Examples

3 General Examples Access Control

4 Concrete Examples

4 Concrete Examples Mobile Code Mobile code probably meant something much different in 1998 Here: Java Mobile = portable Does not equal iPhone

4 Concrete Examples Mobile Code Java (1998): “not tamperproof or unbypassable” i.e. you can break boundaries of abstraction depends on the application-space access control for security e.g. executables could be tampered with

4 Concrete Examples Kerberos Malicious software could spoof client-side authentication Need a trusted path to guarantee this can’t happen Client’s password could be obtained

4 Concrete Examples Kerberos Malicious software could spoof client-side authentication Need a trusted path to guarantee this can’t happen Client’s password could be obtained

6 Summary

No single security mechanism will be a solution to security problems but we knew that Modern (1998) computing threats cannot be addressed without secure operating systems they were right Authors hoped to motivate interest in OS security well, people are interested don’t know if it’s their doing or not