CWE-1393 Base Incomplete

Use of Default Password

This vulnerability occurs when a system or device uses a pre-configured, publicly known password for authentication, often for administrative or critical functions.

Definition

What is CWE-1393?

This vulnerability occurs when a system or device uses a pre-configured, publicly known password for authentication, often for administrative or critical functions.
Manufacturers often ship products with default passwords to simplify initial setup and deployment. While convenient, this practice creates a major security risk if administrators fail to change these defaults, allowing attackers to easily bypass authentication by trying common credentials. Attackers actively use widely available lists of default passwords and automated scanning tools to find and exploit these weak points across many systems. This makes using unchanged defaults a high-risk practice that can lead to widespread, rapid compromise within an organization or across multiple deployments of the same product.
Real-world impact

Real-world CVEs caused by CWE-1393

  • CVE-2022-30270

    Remote Terminal Unit (RTU) uses default credentials for some SSH accounts

  • CVE-2022-2336

    OPC Unified Architecture (OPC UA) industrial automation product has a default password

  • CVE-2021-38759

    microcontroller board has default password

  • CVE-2021-44480

    children's smart watch has default passwords allowing attackers to send SMS commands and listen to the device's surroundings

  • CVE-2020-11624

    surveillance camera has default password for the admin account

  • CVE-2018-15719

    medical dental records product installs a MySQL database with a blank default password

  • CVE-2014-9736

    healthcare system for archiving patient images has default passwords for key management and storage databases

  • CVE-2000-1209

    database product installs admin account with default null password, allowing privileges, as exploited by various worms

How attackers exploit it

Step-by-step attacker path

  1. 1

    Identify a code path that handles untrusted input without validation.

  2. 2

    Craft a payload that exercises the unsafe behavior — injection, traversal, overflow, or logic abuse.

  3. 3

    Deliver the payload through a normal request and observe the application's reaction.

  4. 4

    Iterate until the response leaks data, executes attacker code, or escalates privileges.

Vulnerable code example

Vulnerable pseudo

MITRE has not published a code example for this CWE. The pattern below is illustrative — see Resources for canonical references.

Vulnerable pseudo 
// Example pattern — see MITRE for the canonical references.
function handleRequest(input) {
  // Untrusted input flows directly into the sensitive sink.
  return executeUnsafe(input);
}
Secure code example

Secure pseudo

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.
Prevention checklist

How to prevent CWE-1393

  • Requirements Prohibit use of default, hard-coded, or other values that do not vary for each installation of the product - especially for separate organizations.
  • Documentation Ensure that product documentation clearly emphasizes the presence of default passwords and provides steps for the administrator to change them.
  • Architecture and Design Force the administrator to change the credential upon installation.
  • Installation / Operation The product administrator could change the defaults upon installation or during operation.
Detection signals

How to detect CWE-1393

SAST High

Run static analysis (SAST) on the codebase looking for the unsafe pattern in the data flow.

DAST Moderate

Run dynamic application security testing against the live endpoint.

Runtime Moderate

Watch runtime logs for unusual exception traces, malformed input, or authorization bypass attempts.

Code review Moderate

Code review: flag any new code that handles input from this surface without using the validated framework helpers.

Plexicus auto-fix

Plexicus auto-detects CWE-1393 and opens a fix PR in under 60 seconds.

Codex Remedium scans every commit, identifies this exact weakness, and ships a reviewer-ready pull request with the patch. No tickets. No hand-offs.

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Frequently asked questions

Frequently asked questions

What is CWE-1393?

This vulnerability occurs when a system or device uses a pre-configured, publicly known password for authentication, often for administrative or critical functions.

How serious is CWE-1393?

MITRE has not published a likelihood-of-exploit rating for this weakness. Treat it as medium-impact until your threat model proves otherwise.

What languages or platforms are affected by CWE-1393?

MITRE lists the following affected platforms: Not OS-Specific, Not Architecture-Specific, Not Technology-Specific, ICS/OT.

How can I prevent CWE-1393?

Prohibit use of default, hard-coded, or other values that do not vary for each installation of the product - especially for separate organizations. Ensure that product documentation clearly emphasizes the presence of default passwords and provides steps for the administrator to change them.

How does Plexicus detect and fix CWE-1393?

Plexicus's SAST engine matches the data-flow signature for CWE-1393 on every commit. When a match is found, our Codex Remedium agent opens a fix PR with the corrected code, tests, and a one-line summary for the reviewer.

Where can I learn more about CWE-1393?

MITRE publishes the canonical definition at https://cwe.mitre.org/data/definitions/1393.html. You can also reference OWASP and NIST documentation for adjacent guidance.

Related weaknesses

Weaknesses related to CWE-1393

CWE-1392 Parent

Use of Default Credentials

This vulnerability occurs when a system, device, or application relies on pre-configured, publicly known credentials like passwords or…

CWE-1394 Sibling

Use of Default Cryptographic Key

This vulnerability occurs when a system uses a pre-configured, publicly known cryptographic key for security-critical operations instead…

Resources

Further reading

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