Weakness · High
CWE-184: Incomplete List of Disallowed Inputs
What it is
The product implements a protection mechanism that relies on a list of inputs (or properties of inputs) that are not allowed by policy or otherwise require other action to neutralize before additional processing takes place, but the list is incomplete.
- Severity (our rating)
- High
- Likelihood of exploit
- Not rated by MITRE
- Introduced during
- Architecture and Design, Implementation
- Exploited in the wild
- 4 known exploited CVEs
What an attacker can do
- Bypass Protection Mechanism (Access Control)
How to prevent it
Implementation
- Do not rely exclusively on detecting disallowed inputs. There are too many variants to encode a character, especially when different environments are used, so there is a high likelihood of missing some variants. Only use detection of disallowed inputs as a mechanism for detecting suspicious activity. Ensure that you are using other protection mechanisms that only identify "good" input - such as lists of allowed inputs - and ensure that you are properly encoding your outputs.
How to find it
- Black Box. Exploitation of a vulnerability with commonly-used manipulations might fail, but minor variations might succeed.
Exploited in the wild: 4 CVEs
Vulnerabilities caused by CWE-184 that attackers have used, from CISA's Known Exploited Vulnerabilities catalog, newest first.
- CVE-2026-49869Kestra OSS OS Command Injection Vulnerability · added September 2, 2026
- CVE-2024-5217ServiceNow Incomplete List of Disallowed Inputs Vulnerability · added July 29, 2024
- CVE-2022-26871Trend Micro Apex Central Arbitrary File Upload Vulnerability · added March 31, 2022
- CVE-2021-42321 ransomwareMicrosoft Exchange Server Remote Code Execution Vulnerability · added November 17, 2021
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Start freeSource: MITRE Common Weakness Enumeration, CWE version 4.19.1. CWE is a trademark of The MITRE Corporation.