Path Traversal Vulnerability in K3s by Rancher Labs
CVE-2026-54250
What is CVE-2026-54250?
A path traversal vulnerability was identified in the K3s Kubernetes distribution, affecting versions prior to 1.35.3+k3s1, 1.34.6+k3s1, and v1.33.10+k3s1. The issue arises during the decompression of etcd snapshots. If a malicious zip file containing specially crafted names is restored as a compressed etcd snapshot by an administrator, it can lead to unintentional writing of files to arbitrary locations on the filesystem. This poses significant security risks, allowing attackers to manipulate data and access sensitive areas of the system. The vulnerability has been addressed and mitigated in the mentioned later versions.
Affected Version(s)
k3s >= 1.35.0-rc1+k3s1, < 1.35.3+k3s1 < 1.35.0-rc1+k3s1, 1.35.3+k3s1
k3s >= 1.34.0-rc1+k3s1, < 1.34.6+k3s1 < 1.34.0-rc1+k3s1, 1.34.6+k3s1
k3s < 1.33.10+k3s1 < 1.33.10+k3s1