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Weakness · Medium

CWE-908: Use of Uninitialized Resource

What it is

The product uses or accesses a resource that has not been initialized.

Likelihood of exploit: Medium3 exploited in the wildMITRE CWE 4.19.1

Severity (our rating)
Medium
Likelihood of exploit
Medium
Introduced during
Implementation
Exploited in the wild
3 known exploited CVEs

In more detail

When a resource has not been properly initialized, the product may behave unexpectedly. This may lead to a crash or invalid memory access, but the consequences vary depending on the type of resource and how it is used within the product.

What an attacker can do

  • Read Memory (Confidentiality)
  • Read Application Data (Confidentiality)
  • DoS: Crash, Exit, or Restart (Availability)

How to prevent it

Implementation

  • Explicitly initialize the resource before use. If this is performed through an API function or standard procedure, follow all required steps.
  • Pay close attention to complex conditionals that affect initialization, since some branches might not perform the initialization.
  • Avoid race conditions (CWE-362) during initialization routines.

Build and Compilation

  • Run or compile the product with settings that generate warnings about uninitialized variables or data.

How to find it

  • 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.)

CWE-908 on MITRE's CWE site

Exploited in the wild: 3 CVEs

Vulnerabilities caused by CWE-908 that attackers have used, from CISA's Known Exploited Vulnerabilities catalog, newest first.

All known exploited vulnerabilities

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Source: MITRE Common Weakness Enumeration, CWE version 4.19.1. CWE is a trademark of The MITRE Corporation.