CVE-2026-46703: BoxLite: Path Traversal Vulnerability in boxlite Leads to Arbitrary File Write on the Host

Synopsis

A path traversal vulnerability in BoxLite, the sandbox service for running OCI containers inside lightweight virtual machines, allows an unauthenticated attacker to write arbitrary files to the host filesystem. The attack is delivered over the network and requires a user to load a malicious OCI image, which the attacker can distribute through public registries like DockerHub. Successful exploitation enables arbitrary file writes on the host, which leads directly to remote code execution outside the sandbox boundary. No fix version has been published yet; HarborGuard tracks the advisory for patch availability.

HarborGuard Coverage

Exploit Conditions

• Network reachabilityRequired

  The attacker delivers the malicious OCI image over the network, requiring the victim's BoxLite host to be reachable or for the attacker to publish the image to a publicly accessible registry the victim pulls from.

• AuthenticationNot required

  No authentication or account privileges are needed on the target host; the attacker only needs to publish a malicious image to a registry the victim pulls from.

• Victim interactionRequired

  A user must be tricked into pulling and loading the attacker-crafted OCI image, making social engineering or malicious image distribution the delivery mechanism.

• Attack complexityDetail

  Attack complexity is low, meaning the exploit is reliable and places no special environmental conditions or race-condition requirements on the attacker.

Blast Radius

• Writes arbitrary file content to any path on the host filesystem, bypassing the sandbox boundary entirely.
• Overwrites sensitive host files (such as cron jobs, SSH authorized keys, or init scripts) to achieve persistent remote code execution on the host.
• Modifies container runtime configuration or shared library files to affect other containers or processes running on the same host.
• Compromises confidentiality and integrity of all data on the host, and can crash or destabilize host services by overwriting critical system files.