The HTTP/2 protocol allows a denial of service (server resource consumption) because request cancellation can reset many streams quickly, as exploited in the wild in August through October 2023.

Linkerd is an open source, ultralight, security-first service mesh for Kubernetes. In affected versions when the application being run by linkerd is susceptible to SSRF, an attacker could potentially trigger a denial-of-service (DoS) attack by making requests to localhost:4191/shutdown. Linkerd could introduce an optional environment variable to control a token that must be passed as a header. Linkerd should reject shutdown requests that do not include this header. This issue has been addressed in release version edge-24.6.2 and all users are advised to upgrade. There are no known workarounds for this vulnerability.