runc is a CLI tool for spawning and running containers according to the OCI specification. In versions 1.2.7 and below, 1.3.0-rc.1 through 1.3.1, 1.4.0-rc.1 and 1.4.0-rc.2 files, runc would not perform sufficient verification that the source of the bind-mount (i.e., the containers /dev/null) was actually a real /dev/null inode when using the containers /dev/null to mask. This exposes two methods of attack: an arbitrary mount gadget, leading to host information disclosure, host denial of service, container escape, or a bypassing of maskedPaths. This issue is fixed in versions 1.2.8, 1.3.3 and 1.4.0-rc.3.
Weakness
The product, when opening a file or directory, does not sufficiently account for when the file is a symbolic link that resolves to a target outside of the intended control sphere. This could allow an attacker to cause the product to operate on unauthorized files.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Runc | Linuxfoundation | * | 1.2.8 (excluding) |
| Runc | Linuxfoundation | 1.3.0 (including) | 1.3.3 (excluding) |
| Runc | Linuxfoundation | 1.4.0-rc1 (including) | 1.4.0-rc1 (including) |
| Runc | Linuxfoundation | 1.4.0-rc2 (including) | 1.4.0-rc2 (including) |
| Red Hat Enterprise Linux 8 | RedHat | container-tools:rhel8-8100020251112161627.afee755d | * |
| Red Hat Enterprise Linux 9 | RedHat | runc-4:1.2.5-3.el9_6 | * |
| Red Hat Enterprise Linux 9 | RedHat | runc-4:1.3.0-4.el9_7 | * |
| Red Hat Enterprise Linux 9.4 Extended Update Support | RedHat | runc-4:1.2.9-1.el9_4 | * |
| Red Hat OpenShift Container Platform 4.12 | RedHat | runc-4:1.2.9-1.rhaos4.17.el8 | * |
| Red Hat OpenShift Container Platform 4.13 | RedHat | runc-4:1.2.9-1.rhaos4.16.el9 | * |
| Red Hat OpenShift Container Platform 4.13 | RedHat | rhcos-413.92.202511261311-0 | * |
| Red Hat OpenShift Container Platform 4.15 | RedHat | rhcos-415.92.202512100122-0 | * |
| Red Hat OpenShift Container Platform 4.16 | RedHat | runc-4:1.2.9-1.rhaos4.16.el9 | * |
| Red Hat OpenShift Container Platform 4.16 | RedHat | rhcos-416.94.202511191934-0 | * |
| Red Hat OpenShift Container Platform 4.17 | RedHat | runc-4:1.2.9-1.rhaos4.17.el9 | * |
| Red Hat OpenShift Container Platform 4.18 | RedHat | runc-4:1.2.9-1.rhaos4.18.el9 | * |
| Red Hat OpenShift Container Platform 4.18 | RedHat | rhcos-418.94.202511170715-0 | * |
| Runc | Ubuntu | esm-apps/bionic | * |
| Runc | Ubuntu | esm-apps/noble | * |
| Runc | Ubuntu | esm-apps/xenial | * |
| Runc | Ubuntu | esm-infra/focal | * |
| Runc | Ubuntu | jammy | * |
| Runc | Ubuntu | noble | * |
| Runc | Ubuntu | plucky | * |
| Runc | Ubuntu | questing | * |
| Runc | Ubuntu | upstream | * |
| Runc-app | Ubuntu | devel | * |
| Runc-app | Ubuntu | esm-apps/focal | * |
| Runc-app | Ubuntu | esm-apps/jammy | * |
| Runc-app | Ubuntu | jammy | * |
| Runc-app | Ubuntu | noble | * |
| Runc-app | Ubuntu | plucky | * |
| Runc-app | Ubuntu | questing | * |
| Runc-app | Ubuntu | upstream | * |
| Runc-stable | Ubuntu | devel | * |
| Runc-stable | Ubuntu | questing | * |
| Runc-stable | Ubuntu | upstream | * |
Potential Mitigations
- Follow the principle of least privilege when assigning access rights to entities in a software system.
- Denying access to a file can prevent an attacker from replacing that file with a link to a sensitive file. Ensure good compartmentalization in the system to provide protected areas that can be trusted.
Related Attack Patterns
References
- https://github.com/opencontainers/runc/commit/1a30a8f3d921acbbb6a4bb7e99da2c05f8d48522
- https://github.com/opencontainers/runc/commit/5d7b2424072449872d1cd0c937f2ca25f418eb66
- https://github.com/opencontainers/runc/commit/8476df83b534a2522b878c0507b3491def48db9f
- https://github.com/opencontainers/runc/commit/db19bbed5348847da433faa9d69e9f90192bfa64
- https://github.com/opencontainers/runc/security/advisories/GHSA-9493-h29p-rfm2