CWE-261 Base Incomplete

Weak Encoding for Password

Using simple encoding like Base64 to hide a password provides no real security, as it can be easily reversed.

Definition

What is CWE-261?

Using simple encoding like Base64 to hide a password provides no real security, as it can be easily reversed.
This weakness occurs when developers try to protect passwords stored in configuration files or application properties by encoding them with schemes like Base64, hex, or ROT13. While this obscures the password from casual viewing, it is not encryption. Any attacker who discovers the encoded string can trivially decode it back to the original plaintext password, offering no meaningful defense. True password protection requires strong, one-way cryptographic hashing with a salt, or using a dedicated secrets management solution. Encoding is a form of security through obscurity that creates a false sense of safety. Developers should treat any encoded secret as if it were plaintext, because for an attacker, it effectively is.
Auswirkungen in der Praxis

Real-world CVEs caused by CWE-261

Bisher sind in MITREs Katalog keine öffentlichen CVE-Referenzen mit dieser CWE verknüpft.

Wie Angreifer es ausnutzen

Angreiferpfad Schritt für Schritt

  1. 1

    The following code reads a password from a properties file and uses the password to connect to a database.

  2. 2

    This code will run successfully, but anyone with access to config.properties can read the value of password and easily determine that the value has been base 64 encoded. If a devious employee has access to this information, they can use it to break into the system.

  3. 3

    The following code reads a password from the registry and uses the password to create a new network credential.

  4. 4

    This code will run successfully, but anyone who has access to the registry key used to store the password can read the value of password. If a devious employee has access to this information, they can use it to break into the system.

Verwundbares Codebeispiel

Vulnerable Java

The following code reads a password from a properties file and uses the password to connect to a database.

Verwundbar Java 
...
  Properties prop = new Properties();
  prop.load(new FileInputStream("config.properties"));
  String password = Base64.decode(prop.getProperty("password"));
  DriverManager.getConnection(url, usr, password);
  ...
Sicheres Codebeispiel

Secure pseudo

Sicher 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-261

  • Passwords should be encrypted with keys that are at least 128 bits in length for adequate security.
Erkennungssignale

How to detect CWE-261

Automated Static Analysis High

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.)

Plexicus Auto-Fix

Plexicus erkennt CWE-261 automatisch und öffnet in unter 60 Sekunden einen Fix-PR.

Codex Remedium scannt jeden Commit, identifiziert genau diese Schwachstelle und liefert einen reviewer-ready Pull Request mit dem Patch. Keine Tickets. Keine Hand-offs.

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Häufig gestellte Fragen

Frequently asked questions

Was ist CWE-261?

Using simple encoding like Base64 to hide a password provides no real security, as it can be easily reversed.

Wie gravierend ist CWE-261?

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-261 betroffen?

MITRE hat für diese CWE keine betroffenen Plattformen spezifiziert — sie kann in den meisten Anwendungs-Stacks auftreten.

Wie kann ich CWE-261 verhindern?

Passwords should be encrypted with keys that are at least 128 bits in length for adequate security.

Wie erkennt und behebt Plexicus CWE-261?

Die SAST-Engine von Plexicus erkennt die Datenfluss-Signatur von CWE-261 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-261?

MITRE veröffentlicht die kanonische Definition unter https://cwe.mitre.org/data/definitions/261.html. Für ergänzende Hinweise kannst du auch die OWASP- und NIST-Dokumentation heranziehen.

Verwandte Schwachstellen

Weaknesses related to CWE-261

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-523 Sibling

Unprotected Transport of Credentials

This vulnerability occurs when a login page or authentication system transmits user credentials (like usernames and passwords) over a…

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…

Ressourcen

Further reading

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