CVE-2021-21334

mediumpriority · track · 26EPSS 0.019 · 80 %ileDEEURUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
1.95% (80th) EPSS
CVSS 4.3 · medium
Is it mine?
20 products
Check your exposure
Who says so?
6 sources
cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

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.

01

cvss

Technical severity, 0–10. One row per scoring source.

6.3
010

base score 0–10 · higher = more severe · hover a vector to decode

v2.04.3mediumAV:N/AC:M/Au:N/C:P/I:N/A:Nprimary · NVD / NIST USexploitability 8.6 · impact 2.9
v3.16.3mediumCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:Nprimary · NVD / NIST USexploitability 1.8 · impact 4
v3.16.3mediumAV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:Nsecondary · FSTEC (BDU) RU
v3.16.3mediumCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:Nsecondary · ENISA EU
v3.16.3mediumCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:Nsecondary · security-advisories@github.comexploitability 1.8 · impact 4
v3.16.3mediumCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:Nsecondary · OSV
v3.15.8mediumCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N/E:Usecondary · CVSS-BT (t0sche)
02

weaknesses

The CWE weakness classes this flaw belongs to.

03

affected products (20)

Products and version ranges known to be affected.

04

advisories (2)

Vendor and ecosystem advisories describing this.

  • WID-SEC-W-2022-1002Amazon Linux 2: Mehrere SchwachstellenDeutsch2021-12-08csaf · cert_bundDE

    Ein lokaler Angreifer kann mehrere Schwachstellen in Amazon Linux 2 ausnutzen, um Informationen offenzulegen, Dateien zu manipulieren oder falsche Informationen darzustellen.

  • GHSA-6g2q-w5j3-fwh4containerd environment variable leak2024-01-31ghsa · osvUS

    ## Impact 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 ## Patches This vulnerability has been fixed in containerd 1.3.10 and containerd 1.4.4. Users should update to these versions as soon as they are released. ## Workarounds There are no known workarounds. ## For more information If you have any questions or comments about this advisory: * [Open an issue](https://github.com/containerd/containerd/issues/new/choose) * Email us at security@containerd.io if you think you’ve found a security bug.

05

also known as (4)

Other names and identifiers for this entity.

06

sources

Which sources assert this record, and when.

07

references (34)

External citations — patches, advisories, analysis.

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