CVE-2025-9566: Podman Path Traversal Vulnerability

CVE-2025-9566 Overview

CVE-2025-9566 is a path traversal vulnerability in Podman that allows an attacker to leverage the kube play command to overwrite arbitrary host files. The vulnerability is triggered when a Kubernetes YAML file contains a Secret or ConfigMap volume mount that includes a symbolic link pointing to a host file path. This symlink attack can lead to unauthorized modification of critical system files, potentially causing denial of service or compromising system integrity.

Critical Impact

Attackers can overwrite arbitrary host files through malicious Kubernetes manifests, though they cannot control the content written to the target file.

Affected Products

• Podman versions v4.0.0 through v5.6.0
• Red Hat Enterprise Linux and related distributions using affected Podman versions
• OpenShift Container Platform deployments utilizing vulnerable Podman releases

Discovery Timeline

• September 5, 2025 - CVE-2025-9566 published to NVD
• March 19, 2026 - Last updated in NVD database

Technical Details for CVE-2025-9566

Vulnerability Analysis

This vulnerability exploits a weakness in how Podman handles symbolic links within Secret and ConfigMap volume mounts during kube play operations. The flaw is classified as CWE-22 (Improper Limitation of a Pathname to a Restricted Directory), commonly known as path traversal.

When Podman processes a Kubernetes manifest file containing volume definitions, it fails to properly validate symbolic links embedded within Secret or ConfigMap volumes. An attacker who can supply or modify Kubernetes YAML files processed by kube play can craft a malicious manifest containing a symlink that points outside the intended volume boundary to arbitrary locations on the host filesystem.

The attack has an important limitation: while the attacker can control which file gets overwritten, they cannot control the actual content written to that file. This makes the vulnerability primarily useful for denial-of-service attacks by corrupting critical system files, rather than for injecting malicious code or configurations.

Root Cause

The root cause lies in insufficient symlink validation within Podman's volume handling code when processing Secret and ConfigMap mounts. The kube play command did not adequately check whether symbolic links within these volumes resolve to paths outside the intended container boundaries. This oversight allows directory traversal via symlinks, enabling file operations on the host filesystem that should be restricted to the container's namespace.

Attack Vector

The attack requires network access and low-privilege authentication to submit or influence Kubernetes manifests processed by Podman. The attack flow involves:

1. An attacker crafts a malicious Kubernetes YAML file containing a Secret or ConfigMap volume definition
2. Within this volume, a symbolic link is created that points to a sensitive host file path (e.g., /etc/passwd, /etc/shadow, or system configuration files)
3. When podman kube play processes this manifest, it follows the symlink without proper validation
4. The targeted host file is overwritten with volume content, potentially corrupting critical system files

The vulnerability affects integrity and availability of the host system. No confidentiality impact exists as the attacker cannot read host files through this mechanism.

Detection Methods for CVE-2025-9566

Indicators of Compromise

• Unexpected modifications to system files such as /etc/passwd, /etc/shadow, or other critical configuration files
• Kubernetes YAML files containing suspicious symlink definitions within Secret or ConfigMap volumes
• Unusual podman kube play invocations with external or untrusted manifest sources
• System instability or service failures following Podman container deployments

Detection Strategies

• Monitor podman kube play command execution and audit the source of Kubernetes manifests being processed
• Implement file integrity monitoring (FIM) on critical host system files to detect unauthorized modifications
• Review container volume definitions for symlinks that reference absolute paths or use .. traversal sequences
• Deploy runtime security monitoring to detect container processes attempting to access host filesystem paths outside their designated volumes

Monitoring Recommendations

• Enable audit logging for all Podman commands, particularly kube play operations
• Configure SentinelOne Singularity for container workload protection to monitor for suspicious filesystem operations
• Implement alerts for any modifications to system-critical files outside of approved maintenance windows
• Track the origin and integrity of Kubernetes manifest files before processing with kube play

How to Mitigate CVE-2025-9566

Immediate Actions Required

• Upgrade Podman to version v5.6.1 or later, which contains the fix for this vulnerability
• Audit all Kubernetes manifest files used with podman kube play for suspicious symlink definitions
• Restrict access to the podman kube play command to trusted users and automated systems only
• Implement manifest validation policies that reject volume definitions containing symbolic links

Patch Information

The vulnerability was introduced in Podman v4.0.0 and has been fixed in version v5.6.1. The upstream fix is available in GitHub commit 43fbde4. Red Hat has released multiple security advisories addressing this issue, including RHSA-2025:15900, RHSA-2025:16480, and additional updates documented in Red Hat's CVE page for CVE-2025-9566. For complete technical details, refer to the GitHub Security Advisory GHSA-wp3j-xq48-xpjw.

Workarounds

• Avoid using podman kube play with untrusted or externally-sourced Kubernetes manifest files until patching is complete
• Implement strict access controls limiting which users and systems can execute podman kube play commands
• Pre-validate all Kubernetes YAML files to detect and reject any Secret or ConfigMap volumes containing symbolic links
• Run Podman in rootless mode where possible to limit the impact of potential host filesystem modifications

# Verify current Podman version and upgrade if necessary
podman --version
# If version is between v4.0.0 and v5.6.0, upgrade immediately

# On RHEL/CentOS/Fedora systems
sudo dnf update podman

# Verify the upgraded version
podman --version
# Ensure version is v5.6.1 or higher