Cyber Resilience

CWE · MITRE source

CWE-551Incorrect Behavior Order: Authorization Before Parsing and Canonicalization

Abstraction: Base · CVEs in our corpus: 23

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.

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.

Last updated: 04 July 2026 00:28 UTC

Cumulative inbound coverage

How completely the frameworks we cross-walk collectively cover this — the verdict is the strongest single mapping (overlapping partials are not summed); breadth shows the corroboration behind it.

Collective: partial · 1 mapping(s) from 1 framework(s): ATT&CK 1 (partial)

See the full cumulative-coverage rollup →

NIST 800-53 r5 controls that address this weakness (0)AI

Control Title Family Why it addresses this CWE
No NIST controls proposed yet.

MITRE ATT&CK techniques this weakness enables

Our own two-way CWE↔ATT&CK cross-walk — a direct mapping with no public source (the CWE→CAPEC→ATT&CK chain leaves most top weaknesses, incl. XSS and SQLi, mapped to nothing). Drafted by Grok and spot-checked by Claude Opus 4.8.

Direction: other covers this; this covers other (F/M/P = full / mostly / partial).

Top CVEs of this weakness type, ranked by Risk Priority

CVE Risk CVSS EPSS Published
CVE-2021-281648.05.30.82372021-04-01
CVE-2021-281658.07.50.53862021-04-01
CVE-2021-344298.05.30.99302021-07-15
CVE-2023-239247.010.00.03572023-02-01
CVE-2026-2293 UPD7.09.80.00672026-02-27
CVE-2016-20030 UPD7.09.80.00562026-03-16
CVE-2026-33186 UPD7.09.10.01562026-03-20
CVE-2026-28808 UPD7.09.80.00532026-04-07
CVE-2021-327775.58.60.03332021-08-24
CVE-2021-327795.58.60.00952021-08-24
CVE-2021-313845.57.20.01122021-10-19
CVE-2026-4636 UPD5.58.10.00352026-04-02
CVE-2026-22754 UPD5.57.50.00272026-04-22
CVE-2026-40022 UPD5.58.20.00622026-04-27
CVE-2026-39852 UPD5.58.20.00432026-05-05
CVE-2026-44573 UPD5.57.50.00552026-05-13
CVE-2026-44574 UPD5.58.10.00452026-05-13
CVE-2026-44575 UPD5.57.50.01422026-05-13
CVE-2026-45832 UPD5.58.80.00282026-06-12
CVE-2026-50559 UPD5.57.50.00392026-06-19
CVE-2026-579205.57.70.00222026-06-26
CVE-2026-136765.57.50.00272026-06-29
CVE-2026-0707 UPD3.55.30.00362026-01-08