Vulnerability in Containerd
CVE-2021-21334
In containerd (an industry-standard container runtime) before versions 1.3.10 and 1.4.4, containers launched through containerd's CRI implementation (through Kubernetes, crictl, or any other pod/container client that uses the containerd CRI service) that share the same image may receive incorrect environment variables, including values that are defined for other containers. If the affected containers have different security contexts, this may allow sensitive information to be unintentionally shared. If you are not using containerd's CRI implementation (through one of the mechanisms described above), you are not vulnerable to this issue. If you are not launching multiple containers or Kubernetes pods from the same image which have different environment variables, you are not vulnerable to this issue. If you are not launching multiple containers or Kubernetes pods from the same image in rapid succession, you have reduced likelihood of being vulnerable to this issue This vulnerability has been fixed in containerd 1.3.10 and containerd 1.4.4. Users should update to these versions.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.3 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.020 (80.2th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 80th percentile — 80.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.020 · newest: 0.020 · change: 0.000
Affected products
- Containerd — versions < 1.3.10, >= 1.4.0, < 1.4.4
- Linuxfoundation Containerd
- Fedoraproject Fedora — versions 33, 34
Weakness classification (CWE)
Public proof-of-concept exploits
References
- github.com/containerd/containerd/security/advisories/GHSA-6g2q-w5j3-fwh4 (Third Party Advisory)
- github.com/containerd/containerd/releases/tag/v1.4.4 (Third Party Advisory, Release Notes)
- github.com/containerd/containerd/releases/tag/v1.3.10 (Third Party Advisory, Release Notes)
- github.com/containerd/containerd/commit/05f951a3781f4f2c1911b05e61c160e9c30eaa8e (Patch, Third Party Advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- security.gentoo.org/glsa/202105-33 (vendor-advisory, Third Party Advisory)
Frequently asked questions
- What is CVE-2021-21334?
- CVE-2021-21334 is a medium-severity vulnerability in Containerd, classified under Exposure of Resource to Wrong Sphere. CVSS score: 6.3/10. Published 2021-03-10.
- How severe is CVE-2021-21334?
- Medium severity. CVSS v3 base score is 6.3 out of 10.
- Is CVE-2021-21334 known to be exploited?
- 5 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.