CVE-2013-4441
📋 TL;DR
CVE-2013-4441 is a vulnerability in Pwgen's Phonemes mode that generates predictable passwords, enabling attackers to guess passwords via brute-force attacks. This affects systems using Pwgen 2.06 with Phonemes mode for password generation. The vulnerability allows attackers to compromise accounts protected by these weak passwords.
💻 Affected Systems
- Pwgen
📦 What is this software?
Pwgen by Pwgen Project
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise through password guessing leading to unauthorized access to sensitive systems, data exfiltration, or privilege escalation.
Likely Case
Successful brute-force attacks against accounts using passwords generated by vulnerable Pwgen, resulting in unauthorized access to affected systems.
If Mitigated
Limited impact if strong password policies, multi-factor authentication, and proper access controls are implemented alongside patched Pwgen versions.
🎯 Exploit Status
Exploitation requires access to password hashes or authentication endpoints. Attackers can use predictable patterns to optimize brute-force attacks.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.07 and later
Vendor Advisory: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=726578
Restart Required: No
Instructions:
1. Update Pwgen to version 2.07 or later using your package manager. 2. For Debian/Ubuntu: sudo apt-get update && sudo apt-get install pwgen. 3. For Red Hat/CentOS: sudo yum update pwgen. 4. Verify installation with pwgen --version.
🔧 Temporary Workarounds
Disable Phonemes Mode
linuxAvoid using Phonemes mode (-y flag) when generating passwords with Pwgen.
Use standard mode: pwgen [options] instead of pwgen -y [options]
Use Alternative Password Generators
allReplace Pwgen with other secure password generation tools.
Consider using openssl rand -base64 12 or /dev/urandom based generators
🧯 If You Can't Patch
- Implement strong password policies requiring minimum length, complexity, and regular rotation
- Enable multi-factor authentication for all systems using Pwgen-generated passwords
🔍 How to Verify
Check if Vulnerable:
Check Pwgen version with 'pwgen --version'. If version is 2.06, test Phonemes mode predictability by generating multiple passwords with 'pwgen -y 8 5' and checking for patterns.Check Version:
pwgen --versionVerify Fix Applied:
After update, confirm version is 2.07 or later with 'pwgen --version'. Test Phonemes mode to verify improved randomness.📡 Detection & Monitoring
Log Indicators:
- Multiple failed authentication attempts for accounts using predictable password patterns
- Successful logins following pattern-based brute-force attempts
Network Indicators:
- Unusual authentication traffic patterns to systems using Pwgen-generated passwords
SIEM Query:
Authentication logs showing repeated failed attempts with incremental or patterned password guesses🔗 References
- http://www.openwall.com/lists/oss-security/2013/06/06/1
- http://www.openwall.com/lists/oss-security/2013/10/16/15
- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=726578
- https://www.openwall.com/lists/oss-security/2012/01/22/6
- http://www.openwall.com/lists/oss-security/2013/06/06/1
- http://www.openwall.com/lists/oss-security/2013/10/16/15
- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=726578
- https://www.openwall.com/lists/oss-security/2012/01/22/6
