CVE-2024-48957: Libarchive Buffer Overflow Vulnerability

CVE-2024-48957 Overview

CVE-2024-48957 is an out-of-bounds read vulnerability in the execute_filter_audio function within archive_read_support_format_rar.c in libarchive versions before 3.7.5. The vulnerability occurs when processing crafted RAR archive files, where the source pointer (src) can move beyond the destination buffer (dst), resulting in unauthorized memory access.

Critical Impact

Successful exploitation of this vulnerability could allow an attacker to read sensitive information from memory or cause application crashes through crafted RAR archive files, potentially leading to information disclosure or denial of service conditions.

Affected Products

• libarchive versions prior to 3.7.5
• Applications and systems utilizing vulnerable libarchive versions for RAR archive processing
• Linux distributions and package managers incorporating affected libarchive versions

Discovery Timeline

• 2024-10-10 - CVE-2024-48957 published to NVD
• 2025-09-29 - Last updated in NVD database

Technical Details for CVE-2024-48957

Vulnerability Analysis

This vulnerability is classified as CWE-125 (Out-of-Bounds Read) and affects the audio filter execution routine within libarchive's RAR format support. The flaw exists in the execute_filter_audio function, which is responsible for processing audio data within RAR archives. During the filtering operation, the source pointer can exceed the boundaries of the destination buffer, leading to memory access beyond allocated regions.

The vulnerability requires local access with user interaction, meaning an attacker must convince a user to open or process a maliciously crafted RAR archive file. Upon successful exploitation, the vulnerability could compromise confidentiality, integrity, and availability of the affected system.

Root Cause

The root cause of this vulnerability lies in insufficient boundary checking within the execute_filter_audio function. When processing audio filter operations in RAR archives, the code fails to properly validate that the source pointer remains within the bounds of the destination buffer. This allows the src pointer to advance past the legitimate memory region defined by dst, resulting in out-of-bounds memory reads.

The issue stems from the complex pointer arithmetic involved in the audio decompression algorithm, where the relationship between source and destination buffers is not adequately constrained during iterative processing loops.

Attack Vector

The attack vector for CVE-2024-48957 requires local access to the target system. An attacker must craft a malicious RAR archive file containing specially constructed audio filter data that triggers the out-of-bounds condition. The attack scenario typically involves:

1. The attacker creates a RAR archive with malformed audio filter parameters designed to manipulate pointer calculations
2. The victim downloads or receives the crafted archive file
3. When the victim attempts to extract or preview the archive using an application that relies on libarchive, the vulnerable execute_filter_audio function is invoked
4. The malicious data causes the source pointer to move beyond the destination buffer boundaries, resulting in out-of-bounds memory access

The vulnerability mechanism involves improper pointer boundary validation in the RAR audio filter processing routine. When libarchive processes a specially crafted RAR archive, the execute_filter_audio function iterates through audio data using source and destination pointers. Under normal conditions, these pointers should remain within their allocated buffer regions. However, malicious archive data can manipulate the filter parameters such that the source pointer (src) advances beyond the destination buffer (dst), allowing reads from unintended memory locations. For complete technical details, refer to the CVE-2024-48957 Report.

Detection Methods for CVE-2024-48957

Indicators of Compromise

• Unexpected crashes or segmentation faults in applications using libarchive when processing RAR archives
• Memory access violation errors in system logs related to archive extraction operations
• Anomalous RAR archive files with unusual audio filter configurations in headers

Detection Strategies

• Implement version checking for libarchive installations to identify versions prior to 3.7.5
• Deploy file integrity monitoring on critical systems to detect unexpected libarchive binary modifications
• Use application security testing tools to scan for the presence of vulnerable libarchive versions in your software supply chain
• Monitor for unusual RAR file processing patterns or repeated extraction failures

Monitoring Recommendations

• Enable verbose logging for applications that utilize libarchive for archive processing
• Implement runtime application self-protection (RASP) to detect out-of-bounds memory access attempts
• Deploy endpoint detection and response (EDR) solutions configured to monitor for exploitation attempts against memory corruption vulnerabilities
• Establish baseline behavior for archive processing operations to identify anomalous activity

How to Mitigate CVE-2024-48957

Immediate Actions Required

• Update libarchive to version 3.7.5 or later immediately on all affected systems
• Audit applications and dependencies for libarchive usage and prioritize patching
• Implement input validation controls to filter potentially malicious RAR archives before processing
• Consider temporarily disabling RAR archive processing capabilities if immediate patching is not feasible

Patch Information

The vulnerability has been addressed in libarchive version 3.7.5. The fix involves adding proper boundary checks to ensure the source pointer cannot exceed the destination buffer limits during audio filter execution. Organizations should upgrade to version 3.7.5 or later to remediate this vulnerability.

For detailed information about the changes, review the GitHub Release Notes comparing v3.7.4 to v3.7.5 and the GitHub Pull Request #2149 that contains the security fix.

Workarounds

• Restrict processing of RAR archives from untrusted sources until patching is complete
• Implement file type validation and sandboxing for archive extraction operations
• Use alternative archive processing libraries that are not affected by this vulnerability for handling untrusted files
• Deploy application-level controls to quarantine and scan RAR archives before allowing extraction

# Check libarchive version and update on Debian/Ubuntu systems
dpkg -l | grep libarchive
sudo apt update && sudo apt install --only-upgrade libarchive13

# Check libarchive version and update on RHEL/CentOS systems
rpm -qa | grep libarchive
sudo yum update libarchive

# Verify updated version
bsdtar --version