Kubernetes kubelet EUVD-2026-110500

Requires a Windows Kubernetes worker node running an affected kubelet (<=1.34.11, <=1.35.8, <=1.36.4, or 1.37.0) AND an attacker able to create a pod whose volumeMounts subPath is a symbolic link resolving to an attacker-controlled UNC network share; the kubelet's failure to reject UNC symlink targets is the core flaw. The high-value outcome (NTLM relay to impersonate the node) further requires the node to be domain-joined. Limiting factors: Linux nodes are unaffected; non-domain-joined Windows nodes only expose a crackable hash rather than direct relay; the attacker must hold cluster access sufficient to schedule pods and seed the symlink, and must operate the receiving SMB/UNC endpoint. These stacked conditions justify the vendor's AC:H rating.

This is a genuine but conditional issue, best treated as MEDIUM rather than a top-tier priority. The vendor CVSS 3.1 vector (AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:N/A:N, 5.8) already signals two significant limiters: high attack complexity (AC:H) and high privileges required (PR:H), with the payoff being credential disclosure only (C:H, no integrity or availability impact). The scope change (S:C) reflects that the leaked NetNTLMv2 hash belongs to the kubelet's node account, crossing the pod/node trust boundary. There is no EPSS score, no CISA KEV listing, and no public exploit in the provided data - this is 'no public exploit identified at time of analysis.' No SSVC decision data was supplied. The realistic risk hinges on three stacked preconditions rarely all present: Windows worker nodes, the node being domain-joined (needed for NTLM relay/impersonation, the high-value outcome), and an attacker able to place a symlink whose target is an attacker-controlled UNC share. I assess PR:L is more defensible than the vendor's PR:H, since exploitation needs the ability to create pods and seed a symlink into a mounted volume rather than pre-existing high privilege - this would raise the score slightly but the conclusion (targeted, prerequisite-heavy, not mass-exploitable) is unchanged.

An attacker with the ability to schedule pods on a Windows Kubernetes node creates a pod whose volumeMount subPath is a symbolic link resolving to an attacker-controlled UNC share (e.g. \\attacker-host\share). When the kubelet resolves the symlink it does not reject the UNC target and transparently authenticates to the share with NTLM, leaking the NetNTLMv2 hash of the kubelet service account; if the node is domain-joined the attacker relays or cracks it to impersonate the node. No public exploit code is identified at the time of analysis, and the network-facing capture still requires the high-complexity setup described.