CVE-2023-37644

What it actually does

The vulnerability permits a crafted document to trigger an excessively large memory allocation attempt inside png_read_chunk in lib/png.c, resulting in memory exhaustion.

Why it matters to the business

Systems may become unresponsive when processing untrusted documents, causing operational disruption and potential loss of service availability until the process is terminated or the system is restarted.

How an attack unfolds

An attacker crafts a malicious document that, when opened or converted by the affected tool, reaches png_read_chunk and forces an oversized allocation, exhausting available memory and crashing the process.

How to fix it

Update to a fixed version of the affected package. For chromium on Debian 12 install version 126.0.6478.114-1~deb12u1 or later.

How to confirm the fix worked

Verify the installed package version matches or exceeds the fixed release and confirm that processing of the previously triggering document no longer causes excessive memory usage or crashes.

Typical attack path

1. Prepare a specially crafted document targeting the PNG chunk handling path
2. Deliver the document to the victim or host it for download
3. Victim opens or converts the document using the vulnerable software
4. png_read_chunk attempts the oversized allocation and the process terminates

How to detect it

Review process logs and system resource monitors for unexpected high memory consumption or OOM kills when document conversion tools are invoked; inspect any available crash dumps or core files for references to png_read_chunk.

What your security team should do

• Apply the listed fixed package version immediately on all Debian 12 systems running chromium
• Restrict processing of untrusted documents until patches are deployed
• Monitor memory usage of document-processing workflows for anomalous spikes