Apple Container CVE-2026-64773

Exploitation requires that the target container has at least one TCP port published and reachable by the attacker - containers with no published ports are entirely unaffected. The attacker must be able to establish TCP connections to the published port, which in typical deployments means either internet access to a publicly exposed port or network access within a private segment. No authentication is required (CVSS PR:N). No user interaction is needed. There is no requirement for a specific application running inside the container - the vulnerability is in the host-side forwarding proxy layer, not the containerized application. Exploitation is limited to denial-of-service against host memory; there is no confidentiality or integrity impact. The vulnerability does not affect containers using host networking or other network modes that bypass the published-port forwarding proxy.

CVSS 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) accurately reflects the network-reachable, unauthenticated, low-complexity nature of this DoS. However, real-world risk is moderated by deployment context: the vulnerability is only exploitable if the container has published TCP ports accessible to the attacker - containers without published ports are not affected. EPSS of 0.14% at the 4th percentile signals very low observed or predicted exploitation activity, consistent with a niche container runtime and a pure DoS class that attracts fewer opportunistic attackers than RCE or credential-theft vulnerabilities. There is no CISA KEV listing and no POC is known. The primary realistic threat is against internet-exposed containerized services running on Apple's container runtime - a relatively narrow deployment scenario. The combination of high CVSS and very low EPSS is consistent with a theoretically straightforward but currently unweaponized vulnerability in a product with limited enterprise footprint.

An attacker identifies an internet-facing host running Apple's container runtime with one or more published TCP ports serving a containerized application. The attacker opens many simultaneous connections to a published port and begins transmitting data very slowly, artificially prolonging the forwarding proxy's buffer-accumulation phase by either throttling sends or interfering with backend connection establishment timing. Over time, the host's forwarding process accumulates gigabytes of buffered data across these connections, exhausting available RAM and causing the host OS to kill processes or become unresponsive, resulting in a denial of service for all hosted containers. No authentication or exploit code is required - the attack is a deliberate slow-client pattern.