CWE-1316: Fabric-Address Map Allows Programming of Unwarranted Overlaps of Protected and Unprotected Ranges

CWE-1316: Fabric-Address Map Allows Programming of Unwarranted Overlaps of Protected and Unprotected Ranges is a Common Weakness Enumeration (CWE) entry maintained by MITRE. The address map of the on-chip fabric has protected and unprotected regions overlapping, allowing an attacker to bypass access control to the overlapping portion of the protected region. Various ranges can be defined in the system-address map, either in the memory or in Memory-Mapped-IO (MMIO) space. These ranges are usually defined using special range registers that contain information, such as base address and size. Address decoding is the process of determining for which range the incoming transaction is destined. To ensure isolation, ranges containing secret data are access-control protected. Occasionally, these ranges could overlap. The overlap could either be intentional (e.g. due to a limited number of range registers or limited choice in choosing size of the range) or unintentional (e.g. introduced by errors). Some hardware designs allow dynamic remapping of address ranges assigned to peripheral MMIO ranges. In such designs, intentional address overlaps can be created through misconfiguration by malicious software. When protected and unprotected ranges overlap, an attacker could send a transaction and potentially compromise the protections in place, violating the principle of least privilege.

If exploited, CWE-1316 (Fabric-Address Map Allows Programming of Unwarranted Overlaps of Protected and Unprotected Ranges) it can compromise Confidentiality, Integrity, Access Control and Authorization, leading to outcomes such as Bypass Protection Mechanism, Read Memory and Modify Memory.

Recommended mitigations for CWE-1316 include: When architecting the address map of the chip, ensure that protected and unprotected ranges are isolated and do not overlap. When designing, ensure that ranges hardcoded in Register-Transfer Level (RTL) do not overlap. Ranges configured by firmware should not overlap. If overlaps are mandatory because of constraints such as a limited number of registers, then ensure that no assets are present in the overlapped portion. Validate mitigation actions with robust testing.

CWE-1316 can be detected using Automated Dynamic Analysis and Manual Static Analysis. Combining automated tooling with manual review typically yields the best coverage.

CWE-1316 commonly affects Not Language-Specific. Note that weaknesses are often language-agnostic patterns, so secure coding practices apply broadly.

MITRE documents real CVEs mapped to CWE-1316, including CVE-2009-4419. You can look up the full details of each CVE, including CVSS scores and remediation guidance, on our CVE Lookup tool.

A CWE (Common Weakness Enumeration) like CWE-1316 describes a category of software weakness — the underlying flaw type. A CVE (Common Vulnerabilities and Exposures) identifies a specific, real-world vulnerability in a particular product. In short, a CWE is the kind of mistake, and a CVE is an instance of that mistake being found in software.