Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)
CWE-523 Base Incomplete
Unprotected Transport of Credentials
This vulnerability occurs when a login page or authentication system transmits user credentials (like usernames and passwords) over a network without proper encryption, exposing them to interception.
Definition
What is CWE-523?
This vulnerability occurs when a login page or authentication system transmits user credentials (like usernames and passwords) over a network without proper encryption, exposing them to interception.
When credentials travel from a user's browser to your server without encryption, they are sent in plain text. Attackers on the same network can easily intercept this data using simple packet sniffing tools, leading directly to account compromise. This is a fundamental failure to protect the most sensitive part of the user session during its most vulnerable moment—transit.
To prevent this, you must enforce the use of strong, modern encryption for all authentication traffic. Always use HTTPS (TLS/SSL) for your entire login process and application, never falling back to HTTP for any requests containing credentials. Additionally, implement HTTP Strict Transport Security (HSTS) to instruct browsers to always use a secure connection, preventing accidental data leakage.
Auswirkungen in der Praxis
Real-world CVEs caused by CWE-523
Bisher sind in MITREs Katalog keine öffentlichen CVE-Referenzen mit dieser CWE verknüpft.
Wie Angreifer es ausnutzen
Angreiferpfad Schritt für Schritt
- 1
Identifiziere einen Codepfad, der nicht vertrauenswürdige Eingaben ohne Validierung verarbeitet.
- 2
Erzeuge eine Payload, die das unsichere Verhalten auslöst — Injection, Traversal, Overflow oder Logik-Missbrauch.
- 3
Liefere die Payload über einen normalen Request aus und beobachte die Reaktion der Anwendung.
- 4
Iteriere, bis die Antwort Daten preisgibt, Angreifer-Code ausführt oder Berechtigungen eskaliert.
Verwundbares Codebeispiel
Vulnerable pseudo
MITRE hat kein Codebeispiel für diese CWE veröffentlicht. Das untenstehende Muster ist illustrativ — kanonische Referenzen findest du unter Ressourcen.
// Example pattern — see MITRE for the canonical references.
function handleRequest(input) {
// Untrusted input flows directly into the sensitive sink.
return executeUnsafe(input);
} Sicheres Codebeispiel
Secure pseudo
// Validate, sanitize, or use a safe API before reaching the sink.
function handleRequest(input) {
const safe = validateAndEscape(input);
return executeWithGuards(safe);
} What changed: the unsafe sink is replaced (or the input is validated/escaped) so the same payload no longer triggers the weakness.
Präventions-Checkliste
How to prevent CWE-523
- Operation / System Configuration Enforce SSL use for the login page or any page used to transmit user credentials or other sensitive information. Even if the entire site does not use SSL, it MUST use SSL for login. Additionally, to help prevent phishing attacks, make sure that SSL serves the login page. SSL allows the user to verify the identity of the server to which they are connecting. If the SSL serves login page, the user can be certain they are talking to the proper end system. A phishing attack would typically redirect a user to a site that does not have a valid trusted server certificate issued from an authorized supplier.
Erkennungssignale
How to detect CWE-523
CWE-523
Don't catalog this weakness. Prove it's reachable.
Plexicus turns CWE catalogs into evidence: every CWE-pattern is matched against your real code graph, reach is proven on a sandbox clone, and verified findings ship as reviewed PRs.
Häufig gestellte Fragen Was ist CWE-523?
Wie gravierend ist CWE-523?
Welche Sprachen oder Plattformen sind von CWE-523 betroffen?
Wie kann ich CWE-523 verhindern?
Wie erkennt und behebt Plexicus CWE-523?
Wo erfahre ich mehr über CWE-523?
Frequently asked questions
Was ist CWE-523?
This vulnerability occurs when a login page or authentication system transmits user credentials (like usernames and passwords) over a network without proper encryption, exposing them to interception.
Wie gravierend ist CWE-523?
MITRE hat für diese Schwachstelle keine Exploit-Wahrscheinlichkeit veröffentlicht. Behandle sie als mittlere Auswirkung, bis dein Threat Model anderes belegt.
Welche Sprachen oder Plattformen sind von CWE-523 betroffen?
MITRE hat für diese CWE keine betroffenen Plattformen spezifiziert — sie kann in den meisten Anwendungs-Stacks auftreten.
Wie kann ich CWE-523 verhindern?
Enforce SSL use for the login page or any page used to transmit user credentials or other sensitive information. Even if the entire site does not use SSL, it MUST use SSL for login. Additionally, to help prevent phishing attacks, make sure that SSL serves the login page. SSL allows the user to verify the identity of the server to which they are connecting. If the SSL serves login page, the user can be certain they are talking to the proper end system. A phishing attack would typically redirect…
Wie erkennt und behebt Plexicus CWE-523?
Die SAST-Engine von Plexicus erkennt die Datenfluss-Signatur von CWE-523 bei jedem Commit. Bei einem Treffer öffnet unser Codex-Remedium-Agent einen Fix-PR mit korrigiertem Code, Tests und einer einzeiligen Zusammenfassung für den Reviewer.
Wo erfahre ich mehr über CWE-523?
MITRE veröffentlicht die kanonische Definition unter https://cwe.mitre.org/data/definitions/523.html. Für ergänzende Hinweise kannst du auch die OWASP- und NIST-Dokumentation heranziehen.
Verwandte Schwachstellen
Weaknesses related to CWE-523
CWE-522 Parent
Insufficiently Protected Credentials
This vulnerability occurs when an application handles sensitive credentials like passwords or API keys in an insecure way, making them…
CWE-256 Sibling
Plaintext Storage of a Password
This vulnerability occurs when an application stores user passwords as readable text instead of using secure, one-way hashing. This…
CWE-257 Sibling
Storing Passwords in a Recoverable Format
This vulnerability occurs when an application stores user passwords in a format that can be easily reversed or decrypted back to their…
CWE-260 Sibling
Password in Configuration File
This vulnerability occurs when an application stores sensitive passwords directly within a configuration file, making them easily readable…
CWE-261 Sibling
Weak Encoding for Password
Using simple encoding like Base64 to hide a password provides no real security, as it can be easily reversed.
CWE-549 Sibling
Missing Password Field Masking
This vulnerability occurs when an application fails to hide password characters as they are typed, making them visible to anyone who can…
CWE-312 Peer
Cleartext Storage of Sensitive Information
This vulnerability occurs when an application stores sensitive data like passwords, credit card numbers, or personal information in plain…
Ressourcen
Further reading
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Bereit zu validieren, was zählt.
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