CVE-2026-76654
Description
A flaw was found in Kubernetes kubelet on Windows nodes. When kubelet resolves a volume subPath that is a symbolic link, it does not reject an ordinary UNC network path. Following that link causes Windows to authenticate to the remote share with NTLM, exposing the NetNTLMv2 hash of the kubelet account. That hash may be cracked or, if the node is domain-joined, used in an NTLM relay.
Statement
Only Windows workers are in scope. WMCO is what ships and installs kubelet.exe on those nodes. The Linux kubelet used on control plane and RHCOS workers does not include the vulnerable Windows path.
Mitigation
Clusters with no Windows nodes need no change.
These steps reduce exposure:
- Limit who can create pods that schedule onto Windows nodes.
- Prevent Windows nodes from opening SMB/UNC connections to untrusted networks.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5.8 | N/A | N/A |
| Attack Vector | Network | N/A | N/A |
| Attack Complexity | High | N/A | N/A |
| Privileges Required | High | N/A | N/A |
| User Interaction | None | N/A | N/A |
| Scope | Changed | N/A | N/A |
| Confidentiality | High | N/A | N/A |
| Integrity Impact | None | N/A | N/A |
| Availability Impact | None | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:N/A:N
Understanding the Weakness (CWE)
Confidentiality,Integrity,Access Control
Technical Impact: Read Files or Directories; Modify Files or Directories; Bypass Protection Mechanism
An attacker may be able to traverse the file system to unintended locations and read or overwrite the contents of unexpected files. If the files are used for a security mechanism then an attacker may be able to bypass the mechanism.
Other
Technical Impact: Execute Unauthorized Code or Commands
Windows simple shortcuts, sometimes referred to as soft links, can be exploited remotely since a ".LNK" file can be uploaded like a normal file. This can enable remote execution.
Frequently Asked Questions
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