Weakness · Medium

CWE-820: Missing Synchronization

What it is

The product utilizes a shared resource in a concurrent manner but does not attempt to synchronize access to the resource.

MITRE CWE 4.19.1

Severity (our rating)
Medium
Likelihood of exploit
Not rated by MITRE
Introduced during
Implementation
Exploited in the wild
No CVE in CISA's catalog

In more detail

If access to a shared resource is not synchronized, then the resource may not be in a state that is expected by the product. This might lead to unexpected or insecure behaviors, especially if an attacker can influence the shared resource.

What an attacker can do

  • Modify Application Data (Integrity, Confidentiality, Other)
  • Read Application Data (Integrity, Confidentiality, Other)
  • Alter Execution Logic (Integrity, Confidentiality, Other)

How to prevent it

MITRE lists no specific mitigation for this weakness. Treat it like its parent weaknesses below: validate input, keep the design simple and review the code where it could appear.

CWE-820 on MITRE's CWE site

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