CVE-2023-46566

What it actually does

Remote unauthenticated attacker triggers a buffer overflow in the parse method of TftpPacketFactory by supplying a crafted TFTP packet, resulting in denial of service with no impact on confidentiality or integrity.

Why it matters to the business

Application availability is disrupted, causing service outages for any system relying on the affected TFTP parsing component until the process is restarted or the flaw is addressed.

How an attack unfolds

An attacker sends a specially crafted TFTP packet over the network to the parse function; the missing bounds check allows the overflow to occur, crashing the service without requiring authentication or user interaction.

How to fix it

Upgrade owasp/nodegoat (GIT) to commit 4a4d1db74c63fb4ff8d366551c3af006c25ead12 or later; if tftpy is used as a dependency, ensure the library is updated to a version containing the corrected parse logic.

How to confirm the fix worked

Confirm the running code includes commit 4a4d1db74c63fb4ff8d366551c3af006c25ead12; test by sending both valid and oversized TFTP packets and verifying the service remains responsive without crashing.

Typical attack path

1. Identify a reachable service using the vulnerable TFTP packet parsing code
2. Craft and transmit a malformed TFTP packet targeting the parse function
3. Trigger the buffer overflow leading to process crash or hang
4. Repeat to maintain denial of service

How to detect it

Review application and system logs for unexpected crashes or restarts of processes handling TFTP traffic; look for repeated malformed packet patterns in network captures around the time of outages.

What your security team should do

• Apply the listed commit update immediately across all instances
• Add network segmentation or input validation controls around TFTP services until patched
• Monitor for availability alerts on affected services