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CWE-551

誤った動作順序:解析と正準化の前の認証

Incorrect Behavior Order: Authorization Before Parsing and Canonicalization
脆弱性 作成中
JA

ウェブサーバーが、リクエストされた URL を完全に解析してから認可を確認しない場合、攻撃者は認可保護をバイパスできる可能性があります。

例えば、文字列/./と/はどちらもカレントディレクトリを意味する。SomeDirectoryが保護されたディレクトリで、攻撃者が/./SomeDirectoryをリクエストした場合、認証チェックが実行される前に/./が/に変換されなければ、攻撃者はリソースにアクセスできる可能性があります。

EN

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.

Scope: Access Control / Impact: Bypass Protection Mechanism
URL Inputs should be decoded and canonicalized to the application's current internal representation before being validated and processed for authorization. Make sure that your application does not decode the same input twice. Such errors could be used to bypass allowlist schemes by introducing dangerous inputs after they have been checked.
MITRE公式ページ — CWE-551