CVE-2024-0727: OpenSSL PKCS12 DOS Vulnerability

CVE-2024-0727 Overview

Processing a maliciously formatted PKCS12 file may lead OpenSSL to crash, resulting in a potential Denial of Service (DoS) attack. Applications loading PKCS12 files from untrusted sources might terminate abruptly due to a NULL pointer dereference in OpenSSL.

Critical Impact

This vulnerability can cause applications that process PKCS12 files from untrusted sources to crash, leading to Denial of Service.

Affected Products

• Openssl Openssl
• Not Available
• Not Available

Discovery Timeline

• 2024-01-26T09:15:07.637 - CVE CVE-2024-0727 published to NVD
• 2025-11-03T22:16:34.223 - Last updated in NVD database

Technical Details for CVE-2024-0727

Vulnerability Analysis

The vulnerability arises when OpenSSL processes a PKCS12 file with NULL fields that are not properly checked, leading to a NULL pointer dereference. If exploited, this condition can cause the application to crash.

Root Cause

The root cause of the vulnerability lies in the improper handling of NULL fields in PKCS12 files, leading to a NULL pointer dereference.

Attack Vector

The attack vector is local, as it involves supplying a maliciously formatted PKCS12 file to the vulnerable application that processes PKCS12 files.

// Example exploitation code (sanitized)
PKCS12 *p12 = d2i_PKCS12_fp(fp, NULL);
if (p12 == NULL) {
    // Handle error
    return;
}

Detection Methods for CVE-2024-0727

Indicators of Compromise

• Unexpected application crashes
• Logs indicating null pointer dereference errors
• Abnormal application termination

Detection Strategies

Monitoring application logs for signs of null pointer dereferences in OpenSSL can help detect exploitation attempts. Tools that analyze system call patterns can also flag anomalies indicative of this vulnerability.

Monitoring Recommendations

Implement log analysis and anomaly detection systems to continually monitor for signs of exploitation, such as irregular process exits or null dereference logs.

How to Mitigate CVE-2024-0727

Immediate Actions Required

• Validate all PKCS12 files before processing.
• Restrict PKCS12 file sources to trusted suppliers.
• Update OpenSSL to the latest patched version.

Patch Information

Apply the patches available at:

• Patch 1

Workarounds

Ensure strict validation of PKCS12 files to filter out potentially harmful formats. Employ monitoring solutions to detect and mitigate unauthorized file processing.

# Configuration example
echo "Implement strict PKCS12 file validations before processing." > /etc/openssl/policies