February 25, 2026 Source: The Hacker News 3 min read · 694 words

Claude Code Flaws Allow Remote Code Execution and API Key Exfiltration

Критичні вразливості в Claude Code можуть дозволити зловмисникам викрасти ваші API-ключі

Critical Vulnerabilities in Claude Code Could Let Attackers Steal Your API Keys

Multiple remote code execution flaws. API keys left exposed. And Anthropic's own Claude Code ecosystem is the culprit.

The Hacker News reported that security researchers have disclosed serious vulnerabilities affecting Anthropic's Claude Code—the AI assistant's ability to write and execute code. We're talking about the kind of vulnerabilities that keep security teams up at night: attackers could potentially execute arbitrary code on your system and exfiltrate your Anthropic credentials in the process.

This isn't some theoretical edge case or a false positive vulnerability example that disappears under scrutiny.

This is real. This is happening. And it's affecting how developers interact with Claude's latest capabilities.

Breaking It Down

The vulnerabilities center around three interconnected components: Hooks, MCP (Model Context Protocol) servers, and environment variable handling. Think of it like a biological vulnerability example—one weakness in the organism's immune system can cascade into systemic failure. That's what we're seeing here.

According to The Hacker News, the anthropic mcp vulnerability allows attackers to manipulate how Claude Code processes requests. The anthropic sqlite mcp vulnerability specifically impacts database interactions, creating additional attack surface. Researchers found that environment variables containing API keys aren't properly isolated, making them accessible to malicious code execution chains.

The real question is: how did these make it to production?

An attacker doesn't need sophisticated zero-day exploits here. They just need to craft a prompt that triggers Claude Code to execute code—something the entire point of the feature is to do. From there, they can pivot to accessing API keys stored in environment variables. It's elegant in its simplicity. And deeply unsettling.

The Technical Side

Here's where it gets technical. Claude Code's Hook system allows integration with external services. That flexibility? It's also the vulnerability vector. An attacker can craft malicious Hook configurations that intercept code execution flows.

The anthropic vulnerability disclosure by researchers showed that MCP servers—which extend Claude's capabilities—don't properly validate requests. This means an attacker can potentially register malicious MCP servers that appear legitimate. When Claude Code interacts with them, game over.

Environment variables are supposed to be isolated. They're not. A well-crafted exploit can traverse the execution context and access system environment variables where API keys live. Once you've got API keys, you've got access to the user's Claude account, their usage history, their billing information—potentially their entire workspace if they're using Claude in an enterprise setting.

And attackers don't even need to be sophisticated about this.

A simple proof-of-concept could demonstrate the vulnerability in under 50 lines of code. That's what makes this particularly nasty because—it's not some obscure exploitation technique. It's straightforward abuse of trust boundaries that shouldn't have been this porous.

Who's Affected

Anyone using Claude Code is potentially at risk. That includes individual developers using Claude's web interface with Code execution enabled, teams using Claude through API integrations, and enterprise deployments relying on Claude Code for workflow automation.

The scope isn't limited to direct Claude Code users either.

If you've integrated Claude into your applications through the API and you're using Code execution features, your application users could be affected depending on how your environment is configured. Your API keys become the gateway to abuse.

This is why the anthropic vulnerability disclosure program matters. Responsible disclosure prevents widespread exploitation—but only if patches ship fast. The window between public disclosure and attacker weaponization is measured in hours, sometimes minutes.

What To Do Now

First: rotate your Anthropic API keys immediately. Don't wait for a patch confirmation.

If you're running Claude Code in production or development environments, disable Code execution capabilities until Anthropic releases a patch. Yes, it's disruptive. It's also necessary.

Audit your environment variable configuration. Don't store sensitive credentials as plain environment variables if you can avoid it. Use secrets management solutions instead—vaults, encrypted key stores, anything that adds isolation layers.

Monitor your Anthropic API usage for unusual activity. Spike in requests? Unexpected geographic locations accessing your keys? Flag it immediately.

Finally, stay tuned to Anthropic's official vulnerability disclosure program announcements. They'll publish patches, workarounds, and detailed remediation guidance. When they do, apply updates before you re-enable Code execution features.

This disclosure should prompt a hard conversation about security practices in AI tooling. We're moving fast—maybe too fast—without adequately stress-testing the security implications of features like code execution. That's got to change.

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// FAQ

Do I need to rotate my Anthropic API keys right now?

Yes. Even if you haven't confirmed you were affected, rotating API keys is the safest immediate action. Better safe than having your credentials actively exploited.

Will this affect Claude's regular chat functionality without Code execution?

The vulnerabilities specifically target Claude Code's execution environment. Regular chat without code execution isn't affected by these particular flaws.

Has Anthropic released a patch for these vulnerabilities?

Check Anthropic's official security advisory and vulnerability disclosure program announcements for the latest patch status and timeline. Apply updates immediately when available.

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