CWE-1331: Improper Isolation of Shared Resources in… | Glexia
CWE-1331 (Improper Isolation of Shared Resources in Network On Chip (NoC)) weakness overview with consequences, detection methods, mitigations, related CVEs and…
Glexia's Take · Automated analysis
CWE-1331: Improper Isolation of Shared Resources in Network On Chip (NoC)
Improper Isolation of Shared Resources in Network On Chip (NoC) represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.
Executive Impact
- Confidentiality Availability: DoS: Resource Consumption (Other) Varies by Context Other: Attackers may infer data that belongs to a trusted agent. The methods used to perform this attack may result in noticeably increased resource consumption.
Developer Pattern
CWE-1331 is the kind of defect developers can usually prevent with explicit validation, safer framework defaults, and tests that exercise hostile input or unsafe state transitions.
Automation confidence
high confidence from CWE-1331, 4.20.
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Official CWE Definition
CWE-1331: Improper Isolation of Shared Resources in Network On Chip (NoC)
The Network On Chip (NoC) does not isolate or incorrectly isolates its on-chip-fabric and internal resources such that they are shared between trusted and untrusted agents, creating timing channels.
Typically, network on chips (NoC) have many internal resources that are shared between packets from different trust domains. These resources include internal buffers, crossbars and switches, individual ports, and channels. The sharing of resources causes contention and introduces interference between differently trusted domains, which poses a security threat via a timing channel, allowing attackers to infer data that belongs to a trusted agent. This may also result in introducing network interference, resulting in degraded throughput and latency.
Developer And Remediation Guidance
How teams prevent and detect this weakness
Causes
- Consider a NoC that implements a one-dimensional mesh network with four nodes. This supports two flows: Flow A from node 0 to node 3 (via node 1 and node 2) and Flow B from node 1 to node 2. Flows A and B share a common link between Node 1 and Node 2. Only one flow can use the link in each cycle. One of the masters to this NoC implements a cryptographic algorithm (RSA), and another master to the NoC is a core that can be exercised by an attacker. The RSA algorithm performs a modulo multiplication of two large numbers and depends on each bit of the secret key. The algorithm examines each bit in the secret key and only performs multiplication if the bit is 1. This algorithm is known to be prone to timing attacks. Whenever RSA performs multiplication, there is additional network traffic to the memory controller. One of the reasons for this is cache conflicts. Since this is a one-dimensional mesh, only one flow can use the link in each cycle. Also, packets from the attack program and the RSA program share the output port of the network-on-chip. This contention results in network interference, and the throughput and latency of one flow can be affected by the other flow's demand. There may be different ways to fix this particular weakness.
Remediation
- Architecture and Design Implementation: Implement priority-based arbitration inside the NoC and have dedicated buffers or virtual channels for routing secret data from trusted agents.
Detection
- Manual Analysis: Providing marker flags to send through the interfaces coupled with examination of which users are able to read or manipulate the flags will help verify that the proper isolation has been achieved and is effective.
Mappings
Related CVEs, CWEs, and ATT&CK context
Related CWEs
ATT&CK Relevance
ATT&CK relevance is shown only when reviewed or responsibly inferred.