CVE-2020-8551: K8s.io/kubernetes Remote Code Execution Vulnerability

Q: What is CVE-2020-8551?

CVE-2020-8551 is a security vulnerability in K8s.io/kubernetes involving Allocation of Resources Without Limits or Throttling and Uncontrolled Memory Allocation in Kubernetes under CWE-789: Memory Allocation with Excessive Size Value.

Q: Which K8s.io/kubernetes versions are affected?

Affected versions include releases prior to 1.15.10, 1.16.6, 1.17.2 across affected packages: k8s.io/kubernetes.

Q: What version fixes CVE-2020-8551?

Upgrading to 1.15.10, 1.16.6, 1.17.2 (or the latest patched release for your respective branch) resolves the vulnerability.

Q: Is k8s.io/kubernetes affected?

Yes, k8s.io/kubernetes is affected in releases prior to 1.15.10, 1.16.6, 1.17.2. Upgrade your dependency to 1.15.10, 1.16.6, 1.17.2 or later.

Q: What is the CVSS score of CVE-2020-8551?

CVE-2020-8551 has a CVSS v3.1 base score of 4.3 (MODERATE) with vector string CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.

Q: What CWE is associated with CVE-2020-8551?

CVE-2020-8551 is classified under CWE-789: Memory Allocation with Excessive Size Value (The product allocates memory based on an untrusted, large size value, but it does not ensure that the size is within expected limits, allowing arbitrary amounts of memory to be allocated.).

Q: How can I check Go dependencies for CVE-2020-8551?

Run the dependency tree command: 'inspect dependencies for k8s.io/kubernetes'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.

MODERATE

Advisory Identifier: GHSA-qhm4-jxv7-j9pq

CVSS 4.3

CWE-789 CWE-770

Published 2022-02-15

Advisory Summary

CVE-2020-8551 is a MODERATE (CVSS 4.3) remote code execution vulnerability (CWE-789: Memory Allocation with Excessive Size Value) affecting K8s.io/kubernetes libraries in the Go ecosystem. The issue involves allocation of resources without limits or throttling and uncontrolled memory allocation in kubernetes. Remediation is available by upgrading affected packages to version 1.15.10, 1.16.6, 1.17.2.

CVE-2020-8551 at a Glance

CVE Identifier CVE-2020-8551

GHSA Identifier GHSA-qhm4-jxv7-j9pq

Severity MODERATE

CVSS v3.1 Base Score 4.3

CWE Classification CWE-789: Memory Allocation with Excessive Size Value

Affected Product K8s.io/kubernetes

Package Ecosystem Go

Published Date 2022-02-15

Last Updated 2023-01-27

Security Impact

CVSS: 4.3

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L).

Attack Vector Adjacent (AV:A)

Attack Complexity Low (AC:L)

Privileges Required None (PR:N)

User Interaction None (UI:N)

Scope Unchanged (S:U)

Confidentiality None (C:N)

Integrity None (I:N)

Availability Low (A:L)

How to Fix CVE-2020-8551

To remediate this vulnerability, upgrade all affected K8s.io/kubernetes dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

k8s.io/kubernetes fixed: 1.15.10

Upgrade k8s.io/kubernetes to 1.15.10

k8s.io/kubernetes fixed: 1.16.6

Upgrade k8s.io/kubernetes to 1.16.6

k8s.io/kubernetes fixed: 1.17.2

Upgrade k8s.io/kubernetes to 1.17.2

Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release:

inspect dependencies for k8s.io/kubernetes

How to Check if You Are Affected

To determine whether your application is affected by CVE-2020-8551, inspect your project dependencies for K8s.io/kubernetes:

inspect dependencies for k8s.io/kubernetes

Analyze the terminal output to locate any version of K8s.io/kubernetes in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.15.10), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-789: Memory Allocation with Excessive Size Value, where the product allocates memory based on an untrusted, large size value, but it does not ensure that the size is within expected limits, allowing arbitrary amounts of memory to be allocated. In K8s.io/kubernetes, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

The Kubelet component in versions 1.15.0-1.15.9, 1.16.0-1.16.6, and 1.17.0-1.17.2 has been found to be vulnerable to a denial of service attack via the kubelet API, including the unauthenticated HTTP read-only API typically served on port 10255, and the authenticated HTTPS API typically served on port 10250.

CVE-2020-8551 Affected K8s.io/kubernetes Versions

3 component(s)

Fixed Versions:

1.15.101.16.61.17.2

Product / Package	Ecosystem	Affected Versions	Fixed Version
k8s.io/kubernetes golang/k8s.io/kubernetes	Go	≥ 1.15.0 < 1.15.10	1.15.10
k8s.io/kubernetes golang/k8s.io/kubernetes	Go	≥ 1.16.0 < 1.16.6	1.16.6
k8s.io/kubernetes golang/k8s.io/kubernetes	Go	≥ 1.17.0 < 1.17.2	1.17.2

References

NVD — CVE-2020-8551 NVD

https://nvd.nist.gov/vuln/detail/CVE-2020-8551

K8s.io/kubernetes Source Repository REPOSITORY

https://github.com/kubernetes/kubernetes/issues/89377

K8s.io/kubernetes Source Repository REPOSITORY

https://github.com/kubernetes/kubernetes/pull/87913

Security Fix Commit FIX COMMIT

https://github.com/kubernetes/kubernetes/commit/9802bfcec0580169cffce2a3d468689a407fa7dc

groups.google.com/forum/ WEB

https://groups.google.com/forum/#!topic/kubernetes-security-announce/2UOlsba2g0s

lists.fedoraproject.org/archives/list/packa... WEB

https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/3SOCLOPTSYABTE4CLTSPDIFE6ZZZR4LX

K8s.io/kubernetes Security Information SECURITY

https://security.netapp.com/advisory/ntap-20200413-0003

Frequently Asked Questions

What is CVE-2020-8551?

CVE-2020-8551 is a security vulnerability in K8s.io/kubernetes involving Allocation of Resources Without Limits or Throttling and Uncontrolled Memory Allocation in Kubernetes under CWE-789: Memory Allocation with Excessive Size Value.

Which K8s.io/kubernetes versions are affected?

Affected versions include releases prior to 1.15.10, 1.16.6, 1.17.2 across affected packages: k8s.io/kubernetes.

What version fixes CVE-2020-8551?

Upgrading to 1.15.10, 1.16.6, 1.17.2 (or the latest patched release for your respective branch) resolves the vulnerability.

Is k8s.io/kubernetes affected?

Yes, k8s.io/kubernetes is affected in releases prior to 1.15.10, 1.16.6, 1.17.2. Upgrade your dependency to 1.15.10, 1.16.6, 1.17.2 or later.

What is the CVSS score of CVE-2020-8551?

CVE-2020-8551 has a CVSS v3.1 base score of 4.3 (MODERATE) with vector string CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.

What CWE is associated with CVE-2020-8551?

CVE-2020-8551 is classified under CWE-789: Memory Allocation with Excessive Size Value (The product allocates memory based on an untrusted, large size value, but it does not ensure that the size is within expected limits, allowing arbitrary amounts of memory to be allocated.).

How can I check Go dependencies for CVE-2020-8551?

Run the dependency tree command: 'inspect dependencies for k8s.io/kubernetes'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.

Machine-readable OSV JSON OSV v1.5 Schema

Normalized schema output

View Raw JSON

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-qhm4-jxv7-j9pq",
  "modified" : "2023-01-27T21:42:48Z",
  "published" : "2022-02-15T01:57:18Z",
  "aliases" : [ "CVE-2020-8551" ],
  "summary" : "Allocation of Resources Without Limits or Throttling and Uncontrolled Memory Allocation in Kubernetes",
  "details" : "The Kubelet component in versions 1.15.0-1.15.9, 1.16.0-1.16.6, and 1.17.0-1.17.2 has been found to be vulnerable to a denial of service attack via the kubelet API, including the unauthenticated HTTP read-only API typically served on port 10255, and the authenticated HTTPS API typically served on port 10250.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "k8s.io/kubernetes"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "1.15.0"
      }, {
        "fixed" : "1.15.10"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Go",
      "name" : "k8s.io/kubernetes"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "1.16.0"
      }, {
        "fixed" : "1.16.6"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Go",
      "name" : "k8s.io/kubernetes"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "1.17.0"
      }, {
        "fixed" : "1.17.2"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2020-8551"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/kubernetes/kubernetes/issues/89377"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/kubernetes/kubernetes/pull/87913"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/kubernetes/kubernetes/commit/9802bfcec0580169cffce2a3d468689a407fa7dc"
  }, {
    "type" : "WEB",
    "url" : "https://groups.google.com/forum/#!topic/kubernetes-security-announce/2UOlsba2g0s"
  }, {
    "type" : "WEB",
    "url" : "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/3SOCLOPTSYABTE4CLTSPDIFE6ZZZR4LX"
  }, {
    "type" : "WEB",
    "url" : "https://security.netapp.com/advisory/ntap-20200413-0003"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-770", "CWE-789" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-05-06T21:53:58Z",
    "nvd_published_at" : "2020-03-27T15:15:00Z"
  }
}

CVSS V3

4.3 MODERATE