Vulnerability Description
containerd is an open source container runtime with an emphasis on simplicity, robustness and portability. A bug was found in containerd where container root directories and some plugins had insufficiently restricted permissions, allowing otherwise unprivileged Linux users to traverse directory contents and execute programs. When containers included executable programs with extended permission bits (such as setuid), unprivileged Linux users could discover and execute those programs. When the UID of an unprivileged Linux user on the host collided with the file owner or group inside a container, the unprivileged Linux user on the host could discover, read, and modify those files. This vulnerability has been fixed in containerd 1.4.11 and containerd 1.5.7. Users should update to these version when they are released and may restart containers or update directory permissions to mitigate the vulnerability. Users unable to update should limit access to the host to trusted users. Update directory permission on container bundles directories.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Linuxfoundation | Containerd | < 1.4.11 |
| Fedoraproject | Fedora | 34 |
| Debian | Debian Linux | 11.0 |
Related Weaknesses (CWE)
References
- https://cert-portal.siemens.com/productcert/pdf/ssa-222547.pdf
- https://github.com/containerd/containerd/commit/5b46e404f6b9f661a205e28d59c982d3PatchThird Party Advisory
- https://github.com/containerd/containerd/security/advisories/GHSA-c2h3-6mxw-7mvqThird Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://security.gentoo.org/glsa/202401-31
- https://www.debian.org/security/2021/dsa-5002Third Party Advisory
- https://cert-portal.siemens.com/productcert/pdf/ssa-222547.pdf
- https://github.com/containerd/containerd/commit/5b46e404f6b9f661a205e28d59c982d3PatchThird Party Advisory
- https://github.com/containerd/containerd/security/advisories/GHSA-c2h3-6mxw-7mvqThird Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://security.gentoo.org/glsa/202401-31
- https://www.debian.org/security/2021/dsa-5002Third Party Advisory
FAQ
What is CVE-2021-41103?
CVE-2021-41103 is a vulnerability with a CVSS score of 7.8 (HIGH). containerd is an open source container runtime with an emphasis on simplicity, robustness and portability. A bug was found in containerd where container root directories and some plugins had insuffici...
How severe is CVE-2021-41103?
CVE-2021-41103 has been rated HIGH with a CVSS base score of 7.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2021-41103?
Check the references section above for vendor advisories and patch information. Affected products include: Linuxfoundation Containerd, Fedoraproject Fedora, Debian Debian Linux.