Tag
sandboxing
- Aug 27, 2026 What a Sandbox Proof Establishes and What It Assumes How verification of a sandbox reduces the isolation guarantee to a set of machine-checked lemmas, where the specification gap appears, and why the assumptions are the part that matters. language runtimes
- Jul 22, 2026 Hermetic Actions and Undeclared Inputs An action is hermetic when its output depends only on inputs the graph names. The channels through which that property leaks, the sandboxes that close them, and the cost of closing them. developer tools
- Jun 3, 2026 Syscall Filtering and the Process as a Security Boundary How seccomp filters restrict a process to a fixed set of system calls, why argument inspection is limited by the kernel interface, and where the remaining escape routes lie. language runtimes
- Jan 17, 2026 Hermetic Build Actions: Enforcing That Compilation Reads Only Declared Inputs A declared input list is a promise. Making the promise enforceable means restricting the file system, the clock, and the network, and choosing which of those restrictions is worth its cost. compilers
- Dec 29, 2025 Enforcing Sandbox Policy at BPF LSM Hooks How an eBPF program attached to a kernel LSM hook can decide a security question with access to kernel objects, and why the hook it chooses determines what it can express. virtualization
- Dec 10, 2025 Per-App UID Isolation and the Data Directory Contract How assigning each installed app its own kernel user ID turns file permissions into an application boundary, what the private data directory guarantees, and where the model leaks. mobile computing
- Aug 31, 2025 Hermetic Builds: Isolating the Network, the Clock, and the Filesystem A build that can read the network, the clock, or the ambient filesystem is not a function of its source. Isolation removes those channels and makes the input set explicit. security
- Aug 28, 2025 The Runtime as Reference Monitor: Mediation and the Trusted Base How an interpreter or managed runtime becomes the enforcement point for security policy, which operations escape its mediation, and what the resulting trusted computing base contains. language runtimes
- May 25, 2025 seccomp-BPF and the Filtering of System Calls How a BPF program attached to a process inspects syscall numbers and arguments before dispatch, why argument filtering cannot dereference pointers, and what the return actions cost. operating systems
- May 8, 2025 Permission Grants and Where They Are Enforced How install-time and runtime permission models differ, which layer checks a grant at the moment of use, and why a granted permission can still fail at the call site. mobile computing
- Mar 13, 2025 Mandatory Access Control Above the UID Boundary Why a per-app user ID is not sufficient authorisation, how type enforcement composes with discretionary permissions, and what the policy costs to maintain. mobile computing
- Aug 27, 2024 WebAssembly Imports as the Only Channel to the Host Why a validated module can reach nothing but its own linear memory and its declared imports, and how host functions, tables, and shared memories widen that surface. language runtimes
- Jun 10, 2024 Seccomp Filters and the Cost of Interception How a classic BPF program attached to a thread filters system calls, what it can and cannot inspect, and why tracing every call changes latency by orders of magnitude. operating systems
- Aug 23, 2023 How Capability Sets Split Root Authority The five capability sets a Linux process carries, the transitions between them at exec, and why dropping a capability is not the same as dropping a file permission. virtualization
- Jun 2, 2023 Isolation Boundaries: In-Process, Subprocess, and Sandboxed Tests What leaks between tests that share an address space, what a process boundary actually buys, and why sandboxing undeclared inputs changes which failures are possible. developer tools
- Jun 1, 2023 What a Seccomp Filter Can See of a Syscall The fixed 64-byte record a seccomp filter receives, why the architecture field decides whether the syscall numbers mean anything, and what the filter cost buys. virtualization
- May 4, 2023 Server-Side Template Injection: When Data Reaches an Evaluator Why template engines are interpreters, how a template chosen from user input escalates from text output to code execution, and why sandboxes are the wrong layer. security
- Jan 13, 2023 Landlock Rulesets: Path Hierarchies and Access Masks How Landlock binds access rights to directory hierarchies instead of syscalls, how the handled-access mask determines what a ruleset can enforce, and where the model stops. virtualization
- Oct 4, 2022 Action Precedence When Seccomp Filters Stack How the kernel combines verdicts from multiple attached filters, why the winning action is chosen by a documented ranking rather than by numeric order, and how thread synchronization decides which filters exist at all. virtualization