Base weakness
Incomplete
CWE-551: Incorrect Behavior Order: Authorization Before Parsing and Canonicalization
If a web server does not fully parse requested URLs before it examines them for authorization, it may be possible for an attacker to bypass authorization protection.
Last updated
9
Recorded CVEs
With this primary weakness
0
KEVs
In the CISA KEV catalog
Not rated
Likelihood of exploit
Per MITRE
Base
Abstraction
MITRE classification
Overview
For instance, the character strings /./ and / both mean current directory. If /SomeDirectory is a protected directory and an attacker requests /./SomeDirectory, the attacker may be able to gain access to the resource if /./ is not converted to / before the authorization check is performed.
Real-world CVEs
9 recorded CVEs are caused by CWE-551 (Incorrect Behavior Order: Authorization Before Parsing and Canonicalization). The highest-severity and most recent are shown first. 4 new CWE-551 CVEs have been recorded so far in 2026.