CVE-2022-41843

What it actually does

Crash in convertToType0 in fofi/FoFiType1C.cc when processing malformed Type1C font data in PDF files, resulting in memory corruption and application termination.

Why it matters to the business

Denial of service risk for MariaDB deployments that process untrusted PDF content, potentially disrupting database operations involving PDF handling; low urgency given low exploit probability, long public disclosure period, and absence from known exploitation campaigns.

How an attack unfolds

An attacker supplies a crafted PDF containing malformed Type1C font data that triggers the crash path in the bundled Xpdf code when MariaDB attempts conversion or rendering during query or import operations.

How to fix it

Upgrade mariadb/server to the fixed commit 6d3792a9a2e30201ffbdc977e370e96825b24f3b or later; rebuild from source if using custom GIT builds.

How to confirm the fix worked

Confirm presence of commit 6d3792a9a2e30201ffbdc977e370e96825b24f3b in source tree; attempt reproduction with known-crashing PDF samples in a test environment and verify absence of crash.

Typical attack path

1. Prepare malicious PDF embedding malformed Type1C font stream
2. Cause MariaDB to invoke PDF processing via relevant SQL or storage engine path
3. Trigger convertToType0 crash leading to process termination or service outage

How to detect it

Review MariaDB error logs and process crash dumps for segmentation faults or aborts originating from FoFiType1C.cc or convertToType0; correlate with PDF file ingestion timestamps.

What your security team should do

• Apply the referenced GIT commit immediately on all MariaDB instances that may process PDF data
• Restrict untrusted PDF ingestion until patched
• Monitor application logs for unexpected terminations during font or PDF handling