CVE-2024-56826

What it actually does

Heap buffer overflow in opj_decompress triggered by specific command-line options, resulting in memory corruption that can cause application crash or undefined behavior.

Why it matters to the business

Local users or automated image-processing workflows may experience crashes or unexpected behavior when handling certain inputs, potentially disrupting operations that rely on OpenJPEG for decompression.

How an attack unfolds

An attacker with local access supplies crafted options to the opj_decompress utility, causing a heap buffer overflow that leads to a crash or undefined behavior; no remote or unauthenticated exploitation is indicated.

How to fix it

Upgrade uclouvain/openjpeg to commit e492644fbded4c820ca55b5e50e598d346e850e8 or later; for affected Ubuntu 14.04 systems update chromium-browser to version 58.0.3029.81-0ubuntu0.14.04.1172 or newer packages that incorporate the fix.

How to confirm the fix worked

Confirm the installed OpenJPEG version or commit hash is at or beyond the listed fixed commit; test opj_decompress with known triggering options to verify absence of crash or corruption.

Typical attack path

1. Obtain local access to a system with the vulnerable opj_decompress binary
2. Identify or craft input options that trigger the buffer overflow condition
3. Execute opj_decompress with the malicious options against a target file
4. Observe crash or attempt to leverage resulting undefined behavior

How to detect it

Review system logs and application crash reports for opj_decompress segmentation faults or heap-related errors when the utility is invoked; correlate with command-line history containing decompression operations.

What your security team should do

• Apply the listed fixed versions immediately on all systems using OpenJPEG or dependent packages such as chromium-browser
• Audit local scripts and workflows that invoke opj_decompress to ensure they do not pass untrusted options
• Monitor for application crashes in image-processing pipelines that may indicate attempted exploitation