CVE catalog
CVE-2021-21334
containerd: CVE-2021-21334
- Severity
- Medium · CVSS 6.3
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N - Published
- Source
- [NVD] · [CVE record]
- EPSS
- 1.95% · Oct 25, 2026
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.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | containerd | sid | 2.1.9+ds1-5 | fixed |
| Debian | containerd | forky | 2.1.9+ds1-5 | fixed |
| Debian | containerd | trixie | 1.7.24~ds1-6+deb13u1 | fixed |
| Debian | containerd | trixie-security | 1.7.24~ds1-6+deb13u1 | fixed |
| Debian | containerd | bookworm | 1.6.20~ds1-1+deb12u3 | fixed |
| Debian | containerd | bookworm-security | 1.6.20~ds1-1+deb12u2 | fixed |
| Ubuntu | containerd | pro | 0.2.1-0ubuntu4~16.04 | vulnerable |
| Ubuntu | containerd | pro | 0.2.3-0ubuntu1~16.04 | vulnerable |
| Ubuntu | containerd | pro | 0.2.5-0ubuntu1~16.04.1 | vulnerable |
| Ubuntu | containerd | pro | 1.2.6-0ubuntu1~16.04.2 | vulnerable |
| Ubuntu | containerd | pro | 1.2.6-0ubuntu1~16.04.3 | vulnerable |
| Ubuntu | containerd | pro | 1.2.6-0ubuntu1~16.04.4 | vulnerable |
| Ubuntu | containerd | pro | 1.2.6-0ubuntu1~16.04.5 | vulnerable |
| Ubuntu | containerd | pro | 1.2.6-0ubuntu1~16.04.6 | vulnerable |
| Ubuntu | containerd | pro | 1.2.6-0ubuntu1~16.04.6+esm1 | vulnerable |
| Ubuntu | containerd | pro | 1.2.6-0ubuntu1~16.04.6+esm2 | vulnerable |
| Ubuntu | containerd | pro | 1.2.6-0ubuntu1~16.04.6+esm4 | vulnerable |
| Ubuntu | containerd | pro | 1.2.6-0ubuntu1~16.04.6+esm5 | vulnerable |
| Ubuntu | containerd | pro | 1.2.6-0ubuntu1~16.04.6+esm6 | vulnerable |
| Ubuntu | containerd | pro | 1.2.6-0ubuntu1~16.04.6+esm7 | vulnerable |
| Ubuntu | containerd | 18.04 | 0.2.5-0ubuntu2 | vulnerable |
| Ubuntu | containerd | 18.04 | 1.2.6-0ubuntu1~18.04.1 | vulnerable |
| Ubuntu | containerd | 18.04 | 1.2.6-0ubuntu1~18.04.2 | vulnerable |
| Ubuntu | containerd | 18.04 | 1.3.3-0ubuntu1~18.04.1 | vulnerable |
| Ubuntu | containerd | 18.04 | 1.3.3-0ubuntu1~18.04.2 | vulnerable |
| Ubuntu | containerd | 18.04 | 1.3.3-0ubuntu1~18.04.3 | vulnerable |
| Ubuntu | containerd | 18.04 | 1.3.3-0ubuntu1~18.04.4 | vulnerable |
| Ubuntu | containerd | 18.04 | 1.4.4-0ubuntu1~18.04.2 | vulnerable |
| Ubuntu | containerd | 18.04 | 1.5.2-0ubuntu1~18.04.1 | vulnerable |
| Ubuntu | containerd | 18.04 | 1.5.2-0ubuntu1~18.04.2 | fixed |
| Ubuntu | containerd | 20.04 | 1.2.10-0ubuntu1 | vulnerable |
| Ubuntu | containerd | 20.04 | 1.3.2-0ubuntu1 | vulnerable |
| Ubuntu | containerd | 20.04 | 1.3.3-0ubuntu1 | vulnerable |
| Ubuntu | containerd | 20.04 | 1.3.3-0ubuntu2 | vulnerable |
| Ubuntu | containerd | 20.04 | 1.3.3-0ubuntu2.1 | vulnerable |
| Ubuntu | containerd | 20.04 | 1.3.3-0ubuntu2.2 | vulnerable |
| Ubuntu | containerd | 20.04 | 1.3.3-0ubuntu2.3 | fixed |
| Ubuntu | containerd | 20.04 | 1.2.10-0ubuntu1 | vulnerable |
| Ubuntu | containerd | 20.04 | 1.3.2-0ubuntu1 | vulnerable |
| Ubuntu | containerd | 20.04 | 1.3.3-0ubuntu1 | vulnerable |
| Ubuntu | containerd | 20.04 | 1.3.3-0ubuntu2 | vulnerable |
| Ubuntu | containerd | 20.04 | 1.3.3-0ubuntu2.1 | vulnerable |
| Ubuntu | containerd | 20.04 | 1.3.3-0ubuntu2.2 | vulnerable |
| Ubuntu | containerd | 20.04 | 1.3.3-0ubuntu2.3 | fixed |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | containerd | source | sid | 1.4.4~ds1-1 | not yet assigned | Not reported | Not reported |
| Debian | containerd | source | forky | 1.4.4~ds1-1 | not yet assigned | Not reported | Not reported |
| Debian | containerd | source | trixie | 1.4.4~ds1-1 | not yet assigned | Not reported | Not reported |
| Debian | containerd | source | bookworm | 1.4.4~ds1-1 | not yet assigned | Not reported | Not reported |
| Ubuntu | containerd | deb | 18.04 | 1.5.2-0ubuntu1~18.04.2 | Not reported | UBUNTU-CVE-2021-21334 | Not reported |
| Ubuntu | containerd | deb | 20.04 | 1.3.3-0ubuntu2.3 | Not reported | UBUNTU-CVE-2021-21334 | Not reported |
| Ubuntu | containerd | deb | 20.04 | 1.3.3-0ubuntu2.3 | Not reported | USN-4881-1 | Not reported |
OpenFactory catalog packages
Matching against OpenFactory catalog package versions is in progress.
[Debian 12 (Bookworm)]
- [containerd]Unknown
Details (4)
1.6.20~ds1-1+deb12u3· amd64 · bookwormFixed · Fixed:
1.4.4~ds1-1dsa · containerd · debian · bookworm; dsa · containerd · debian · 12
1.6.20~ds1-1+deb12u3· arm64 · bookwormFixed · Fixed:
1.4.4~ds1-1dsa · containerd · debian · bookworm; dsa · containerd · debian · 12
1.6.20~ds1-1+deb12u2· amd64 · bookworm-securityFixed · Fixed:
1.4.4~ds1-1dsa · containerd · debian · bookworm; dsa · containerd · debian · 12
1.6.20~ds1-1+deb12u2· arm64 · bookworm-securityFixed · Fixed:
1.4.4~ds1-1dsa · containerd · debian · bookworm; dsa · containerd · debian · 12
Source package: [containerd]
Details (4)
1.6.20~ds1-1+deb12u3· all · bookwormFixed · Fixed:
1.4.4~ds1-1dsa · containerd · debian · bookworm; dsa · containerd · debian · 12
1.6.20~ds1-1+deb12u3· all · bookwormFixed · Fixed:
1.4.4~ds1-1dsa · containerd · debian · bookworm; dsa · containerd · debian · 12
1.6.20~ds1-1+deb12u2· all · bookworm-securityFixed · Fixed:
1.4.4~ds1-1dsa · containerd · debian · bookworm; dsa · containerd · debian · 12
1.6.20~ds1-1+deb12u2· all · bookworm-securityFixed · Fixed:
1.4.4~ds1-1dsa · containerd · debian · bookworm; dsa · containerd · debian · 12
[Debian 13 (Trixie)]
- [containerd]Unknown
Details (4)
1.7.24~ds1-6+deb13u1· amd64 · trixieFixed · Fixed:
1.4.4~ds1-1dsa · containerd · debian · 13
1.7.24~ds1-6+deb13u1· arm64 · trixieFixed · Fixed:
1.4.4~ds1-1dsa · containerd · debian · 13
1.7.24~ds1-6+deb13u1· amd64 · trixie-securityFixed · Fixed:
1.4.4~ds1-1dsa · containerd · debian · 13
1.7.24~ds1-6+deb13u1· arm64 · trixie-securityFixed · Fixed:
1.4.4~ds1-1dsa · containerd · debian · 13
Source package: [containerd]
Details (4)
1.7.24~ds1-6+deb13u1· all · trixieFixed · Fixed:
1.4.4~ds1-1dsa · containerd · debian · 13
1.7.24~ds1-6+deb13u1· all · trixieFixed · Fixed:
1.4.4~ds1-1dsa · containerd · debian · 13
1.7.24~ds1-6+deb13u1· all · trixie-securityFixed · Fixed:
1.4.4~ds1-1dsa · containerd · debian · 13
1.7.24~ds1-6+deb13u1· all · trixie-securityFixed · Fixed:
1.4.4~ds1-1dsa · containerd · debian · 13
Observed:
References
- [https://ftp.suse.com/pub/projects/security/csaf/suse-su-2021_1458-1.json]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2021-21334]
- [https://osv.dev/vulnerability/UBUNTU-CVE-2021-21334]
- [https://osv.dev/vulnerability/USN-4881-1]
- [https://security-tracker.debian.org/tracker/CVE-2021-21334]
- [https://security.access.redhat.com/data/csaf/v2/vex/2021/cve-2021-21334.json]
- [https://wid.cert-bund.de/.well-known/csaf/white/2021/wid-sec-w-2022-1002.json]
[CERT-Bund public advisories] · [Debian Security Tracker] · [FIRST EPSS] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]