CVE-2024-11477: 7-Zip Zstandard Decompression RCE Flaw

CVE-2024-11477 Overview

7-Zip Zstandard Decompression Integer Underflow Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of 7-Zip. Interaction with this library is required to exploit this vulnerability, but attack vectors may vary depending on the implementation.

Critical Impact
This vulnerability can lead to remote code execution within the context of the affected application, potentially allowing attackers to control the system.

Affected Products

7-zip 7-zip

Discovery Timeline

Not Available - Vulnerability discovered by Not Available
Not Available - Responsible disclosure to Not Available
Not Available - CVE CVE-2024-11477 assigned
Not Available - 7-zip releases security patch
2024-11-22 - CVE CVE-2024-11477 published to NVD
2025-02-15 - Last updated in NVD database

Technical Details for CVE-2024-11477

Vulnerability Analysis

The vulnerability resides in the Zstandard decompression library due to improper validation of user-supplied data, leading to an integer underflow before memory operations. Exploiting this flaw can allow an attacker to execute code with the privileges of the current process.

Root Cause

The root cause is an integer underflow that occurs when the application fails to validate compressed data size, leading to potential execution of arbitrary code.

Attack Vector

Local exploitation requires manipulating a crafted archive to trigger the vulnerability through file decompression.

cpp

// Example exploitation code (sanitized)
unsigned char data[] = { /* crafted data */ };
size_t size = /* calculated size */;

if (size < data[0]) {
    // Underflow occurs here
    process(data);
}

Detection Methods for CVE-2024-11477

Indicators of Compromise

Unusual 7-Zip process behaviors
Presence of crafted archive files
Unexpected system process privileges

Detection Strategies

Use behavioral analysis to detect abnormal 7-Zip execution, especially when processing new decompression tasks. Implement file integrity monitoring for 7-Zip-related files.

Monitoring Recommendations

Regularly monitor for new additions or modifications to 7-Zip archives. Utilize heuristic-based threat detection to spot unfamiliar decompression activities.

How to Mitigate CVE-2024-11477

Immediate Actions Required

Update to the latest version of 7-Zip
Deploy intrusion detection systems focused on file decompression
Audit file integrity for critical applications

Patch Information

Monitor the official 7-Zip website and advisory platforms for security patches related to CVE-2024-11477.

Workarounds

In environments where patching is not immediately feasible, restrict the use of 7-Zip for processing untrusted archives.

bash

# Configuration example
chmod -x /usr/bin/7z               # Disable 7-Zip temporarily