Weakness · High
CWE-180: Incorrect Behavior Order: Validate Before Canonicalize
What it is
The product validates input before it is canonicalized, which prevents the product from detecting data that becomes invalid after the canonicalization step.
- Severity (our rating)
- High
- Likelihood of exploit
- Not rated by MITRE
- Introduced during
- Implementation
- Exploited in the wild
- No CVE in CISA's catalog
In more detail
This can be used by an attacker to bypass the validation and launch attacks that expose weaknesses that would otherwise be prevented, such as injection.
What an attacker can do
- Bypass Protection Mechanism (Access Control)
How to prevent it
Implementation
- Inputs should be decoded and canonicalized to the application's current internal representation before being validated (CWE-180). Make sure that the application does not decode the same input twice (CWE-174). Such errors could be used to bypass allowlist validation schemes by introducing dangerous inputs after they have been checked.
H2 Security
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Start freeSource: MITRE Common Weakness Enumeration, CWE version 4.19.1. CWE is a trademark of The MITRE Corporation.