CWE-127: Buffer Under-read

low-risk

The product reads from a buffer using buffer access mechanisms such as indexes or pointers that reference memory locations prior to the targeted buffer.

Abstraction: Variant

Common Consequences

Confidentiality Read Memory
Confidentiality Bypass Protection Mechanism

Detection Methods

Automated Static Analysis

Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)

Automated Dynamic Analysis

Use tools that are integrated during compilation to insert runtime error-checking mechanisms related to memory safety errors, such as AddressSanitizer (ASan) for C/C++ [REF-1518].

Real-World Examples (6)

CVE CVSS EPSS KEV
CVE-2020-5360 7.5 2.1%
CVE-2025-32050 5.9 0.9%
CVE-2020-1918 7.5 0.3%
CVE-2025-20359 6.5 0.3%
CVE-2024-10395 8.6 0.3%
CVE-2024-25629 4.4 0.1%
0
/ 100
low-risk
Active Threat 0/50 · Minimal
Exploit Availability 0/50 · Minimal