Security information

The MKE 3.6.15 patch release focuses exclusively on CVE mitigation. To this end, the following middleware component versions have been upgraded to resolve vulnerabilities in MKE:

  • [MKE-11504] Golang 1.21.10

  • [MKE-11502] cri-dockerd 0.3.14

  • [MKE-11482] NGINX Ingress Controller 1.10.1

  • [MKE-11482] Gatekeeper 3.14.2

  • DOCKER_EE_CLI 23.0.11~3

The following table details the specific CVEs addressed, including which images are affected per CVE.



Image mitigated

Problem details from upstream



  • ucp-hyperkube

The protojson.Unmarshal function can enter an infinite loop when unmarshaling certain forms of invalid JSON. This condition can occur when unmarshaling into a message which contains a google.protobuf. Any value, or when the UnmarshalOptions.DiscardUnknown option is set.



  • ucp-hyperkube

Moby is an open-source project created by Docker to enable software containerization. The classic builder cache system is prone to cache poisoning if the image is built FROM scratch. Also, changes to some instructions (most important being HEALTHCHECK and ONBUILD) would not cause a cache miss. An attacker with the knowledge of the Dockerfile someone is using could poison their cache by making them pull a specially crafted image that would be considered as a valid cache candidate for some build steps. 23.0+ users are only affected if they explicitly opted out of Buildkit (DOCKER_BUILDKIT=0 environment variable) or are using the /build API endpoint. All users on versions older than 23.0 could be impacted. Image build API endpoint (/build) and ImageBuild function from is also affected as it the uses classic builder by default. Patches are included in 24.0.9 and 25.0.2 releases.



  • ucp-swarm

  • ucp-azure-ip-allocatior

  • ucp-gatekeeper

  • ucp-node-feature-discovery

An attacker may cause an HTTP/2 endpoint to read arbitrary amounts of header data by sending an excessive number of CONTINUATION frames. Maintaining HPACK state requires parsing and processing all HEADERS and CONTINUATION frames on a connection. When a request’s headers exceed MaxHeaderBytes, no memory is allocated to store the excess headers, but they are still parsed. This permits an attacker to cause an HTTP/2 endpoint to read arbitrary amounts of header data, all associated with a request which is going to be rejected. These headers can include Huffman-encoded data which is significantly more expensive for the receiver to decode than for an attacker to send. The fix sets a limit on the amount of excess header frames we will process before closing a connection.