Overview
CVE-2025-65105 describes a medium severity security vulnerability in Apptainer, an open-source container platform. This flaw allows a container to disable the --security=apparmor:<profile> and --security=selinux:<label> options, potentially bypassing intended security restrictions. This impacts systems where AppArmor or SELinux are relied upon to limit container operations. The vulnerability affects Apptainer versions prior to 1.4.5.
Technical Details
The --security option in Apptainer is designed to allow the root user to apply additional security restrictions to containers, using AppArmor or SELinux profiles/labels. While documentation indicates this is a root-only feature, it functions for unprivileged users on systems where AppArmor or SELinux are enabled. The vulnerability lies in the container’s ability to manipulate this option to disable these restrictions, even when they should be in place. This could allow a container to perform actions that would normally be blocked by AppArmor or SELinux policies.
The vulnerability is related to how Apptainer processes the --security flag. An attacker could potentially supply a malformed or specifically crafted argument to the --security flag, causing Apptainer to ignore or disable the AppArmor or SELinux restrictions.
CVSS Analysis
- CVE ID: CVE-2025-65105
- Severity: MEDIUM
- CVSS Score: 4.5
A CVSS score of 4.5 indicates a medium severity vulnerability. This score reflects the fact that while the vulnerability exists, it requires a specific configuration (AppArmor/SELinux enabled and in use) to be exploitable. The impact is limited by the potential for the container to bypass security policies, rather than achieving full system compromise.
Possible Impact
If exploited, this vulnerability could allow a malicious container to:
- Bypass AppArmor or SELinux policies designed to restrict its actions.
- Access resources or perform operations that it should not be authorized to do.
- Potentially escalate privileges within the container.
The exact impact will depend on the specific AppArmor or SELinux policies in place and the actions the malicious container attempts to perform.
Mitigation and Patch Steps
The recommended mitigation is to upgrade to Apptainer version 1.4.5 or later. This version contains the fix for CVE-2025-65105.
- Upgrade Apptainer: Use your system’s package manager or follow the instructions on the Apptainer website to upgrade to version 1.4.5 or later.
- Verify the fix: After upgrading, verify that the vulnerability is no longer present.
- Review existing AppArmor/SELinux profiles: Ensure that your AppArmor and SELinux profiles are appropriately configured to protect your system.
