CVE-2024-56827: OpenJPEG Buffer Overflow Vulnerability

CVE-2024-56827 Overview

A heap buffer overflow vulnerability has been discovered in the OpenJPEG project affecting the opj_decompress utility. When certain options are specified during JPEG 2000 image decompression, a heap buffer overflow condition may be triggered. This vulnerability can lead to an application crash or other undefined behavior, potentially allowing attackers to cause denial of service on systems processing malicious JPEG 2000 files.

Critical Impact

A locally authenticated attacker can craft a malicious JPEG 2000 file that, when processed with specific options by the opj_decompress utility, triggers a heap buffer overflow leading to application crash or potentially undefined behavior.

Affected Products

• OpenJPEG library (openjpeg)
• Systems using opj_decompress utility
• Red Hat Enterprise Linux and derivatives with affected OpenJPEG packages
• Debian-based distributions with vulnerable OpenJPEG versions

Discovery Timeline

• 2025-01-09 - CVE-2024-56827 published to NVD
• 2025-11-03 - Last updated in NVD database

Technical Details for CVE-2024-56827

Vulnerability Analysis

This vulnerability is classified as CWE-122 (Heap-based Buffer Overflow). The flaw exists in the JPEG 2000 codec implementation within OpenJPEG, specifically in the tile-part marker handling logic. When processing JPEG 2000 files, the opj_j2k_add_tlmarker() function in src/lib/openjp2/j2k.c fails to properly validate that the current tile-part number is within the bounds of the allocated tile-part index array before accessing it.

The attack requires local access with user interaction, meaning a victim must be persuaded to process a specially crafted JPEG 2000 file using the vulnerable opj_decompress utility with specific command-line options. While the vulnerability does not enable data modification, it poses significant availability risks and limited confidentiality exposure through potential memory disclosure.

Root Cause

The root cause lies in insufficient bounds checking within the opj_j2k_add_tlmarker() function. The code accesses the tp_index array using l_current_tile_part as an index without first verifying that this value is smaller than nb_tps (the number of tile parts). This oversight allows an out-of-bounds write to heap memory when a malformed JPEG 2000 file contains tile-part markers with unexpected sequencing.

Attack Vector

The attack vector is local, requiring the attacker to either have local access to the target system or convince a user to process a malicious JPEG 2000 file. The exploitation scenario involves:

1. An attacker crafts a malicious JPEG 2000 (.jp2 or .j2k) file with manipulated tile-part markers
2. The victim uses opj_decompress with specific options to process the file
3. The malformed tile-part data triggers the bounds check failure
4. A heap buffer overflow occurs, causing application crash or undefined behavior

The following patch demonstrates the fix applied to address the vulnerability:

     if (type == J2K_MS_SOT) {
         OPJ_UINT32 l_current_tile_part = cstr_index->tile_index[tileno].current_tpsno;
 
-        if (cstr_index->tile_index[tileno].tp_index) {
+        if (cstr_index->tile_index[tileno].tp_index &&
+                l_current_tile_part < cstr_index->tile_index[tileno].nb_tps) {
             cstr_index->tile_index[tileno].tp_index[l_current_tile_part].start_pos = pos;
         }
 

Source: GitHub OpenJPEG Commit e492644

Detection Methods for CVE-2024-56827

Indicators of Compromise

• Unexpected crashes of opj_decompress or applications using the OpenJPEG library
• Core dumps or crash reports indicating heap corruption in OpenJPEG library functions
• Presence of malformed JPEG 2000 files (.jp2, .j2k) with unusual tile-part marker structures
• Memory access violations in j2k.c or related codec components

Detection Strategies

• Monitor for abnormal termination of processes using OpenJPEG libraries, particularly opj_decompress
• Implement file integrity monitoring to detect suspicious JPEG 2000 files before processing
• Use memory sanitizers (ASan, MSan) in development environments to catch heap overflows early
• Deploy endpoint detection solutions to identify exploitation attempts targeting image processing utilities

Monitoring Recommendations

• Enable crash reporting and centralized logging for applications using OpenJPEG
• Implement anomaly detection for file processing workflows that handle JPEG 2000 images
• Monitor system stability metrics for services that depend on OpenJPEG functionality
• Review audit logs for unusual invocations of opj_decompress with uncommon option combinations

How to Mitigate CVE-2024-56827

Immediate Actions Required

• Update OpenJPEG to the latest patched version containing commit e492644
• Apply vendor-specific security updates from Red Hat (RHSA-2025:7309) or Debian as applicable
• Restrict execution of opj_decompress utility to trusted users and validated input files
• Implement input validation for JPEG 2000 files before processing with OpenJPEG tools

Patch Information

The vulnerability has been addressed in the OpenJPEG project through commit e492644. The fix adds a bounds check to ensure that l_current_tile_part is smaller than nb_tps before accessing the tile-part index array. Major Linux distributions have released security updates:

• Red Hat: Security erratum RHSA-2025:7309 provides the fix for affected RHEL versions
• Debian: A Debian LTS Security Announcement addresses this vulnerability

For tracking and additional details, refer to Red Hat Bugzilla Report #2335174 and GitHub OpenJPEG Issue #1564.

Workarounds

• Avoid processing untrusted JPEG 2000 files with opj_decompress until patches are applied
• Implement sandboxing or containerization for image processing workflows using OpenJPEG
• Use alternative JPEG 2000 decoders temporarily if critical processing cannot be delayed
• Restrict file upload capabilities to prevent malicious JPEG 2000 files from reaching vulnerable systems

# Example: Update OpenJPEG on Red Hat-based systems
sudo yum update openjpeg2

# Example: Update OpenJPEG on Debian-based systems
sudo apt-get update && sudo apt-get upgrade libopenjp2-7

# Verify installed version includes security fix
opj_decompress -h 2>&1 | head -n 1