CVE-2023-39347: Github.com/cilium/cilium Kubernetes Users May Update Pod Vulnerability

MODERATE
Advisory Identifier: GHSA-gj2r-phwg-6rww
CVSS 5.4
CWE-345
Published
Advisory Summary

CVE-2023-39347 is a MODERATE (CVSS 5.4) kubernetes users may update pod vulnerability (CWE-345: Insufficient Verification of Data Authenticity) affecting Github.com/cilium/cilium libraries in the Go ecosystem. The issue involves kubernetes users may update pod labels to bypass network policy. Remediation is available by upgrading affected packages to version 1.13.7, 1.14.2, 1.12.14.

CVE-2023-39347 at a Glance

CVE Identifier CVE-2023-39347
GHSA Identifier GHSA-gj2r-phwg-6rww
Severity MODERATE
CVSS v3.1 Base Score 5.4
CWE Classification CWE-345: Insufficient Verification of Data Authenticity
Affected Product Github.com/cilium/cilium
Package Ecosystem Go
Published Date
Last Updated

Security Impact

CVSS: 5.4

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

Attack Vector Adjacent (AV:A)
Attack Complexity Low (AC:L)
Privileges Required Low (PR:L)
User Interaction None (UI:N)
Scope Changed (S:C)
Confidentiality Low (C:L)
Integrity None (I:N)
Availability Low (A:L)

How to Fix CVE-2023-39347

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

github.com/cilium/cilium fixed: 1.13.7
Upgrade github.com/cilium/cilium to 1.13.7
github.com/cilium/cilium fixed: 1.14.2
Upgrade github.com/cilium/cilium to 1.14.2
github.com/cilium/cilium fixed: 1.12.14
Upgrade github.com/cilium/cilium to 1.12.14
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 github.com/cilium/cilium

How to Check if You Are Affected

To determine whether your application is affected by CVE-2023-39347, inspect your project dependencies for Github.com/cilium/cilium:

inspect dependencies for github.com/cilium/cilium

Analyze the terminal output to locate any version of Github.com/cilium/cilium in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.13.7), 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-345: Insufficient Verification of Data Authenticity, where the product does not sufficiently verify the origin or authenticity of data, in a way that causes it to accept invalid data. In Github.com/cilium/cilium, 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

### Impact An attacker with the ability to update pod labels can cause Cilium to apply incorrect network policies. This issue arises due to the fact that on pod update, Cilium incorrectly uses user-provided pod labels to select the policies which apply to the workload in question. This can affect: * Cilium network policies that use the namespace, service account or cluster constructs to restrict traffic * Cilium clusterwide network policies that use Cilium namespace labels to select the Pod * Kubernetes network policies Non-existent construct names can be provided, which bypass all network policies applicable to the construct. For example, providing a pod with a non-existent namespace as the value of the `io.kubernetes.pod.namespace` label results in none of the namespaced CiliumNetworkPolicies applying to the pod in question. This attack requires the attacker to have [Kubernetes API Server access](https://docs.cilium.io/en/latest/security/threat-model/#kubernetes-api-server-attacker), as described in the Cilium Threat Model. ### Patches This issue affects: - Cilium <= v1.14.1 - Cilium <= v1.13.6 - Cilium <= v1.12.13 This issue has been resolved in: - Cilium v1.14.2 - Cilium v1.13.7 - Cilium v1.12.14 ### Workarounds An admission webhook can be used to prevent pod label updates to the `k8s:io.kubernetes.pod.namespace` and `io.cilium.k8s.policy.*` keys. ### Acknowledgements The Cilium community has worked together with members of Palantir and Isovalent to prepare these mitigations. Special thanks to @odinuge for reporting this issue and to @nebril for the fix. ### For more information If you have any questions or comments about this advisory, please reach out on [Slack](https://docs.cilium.io/en/latest/community/community/#slack). If you think you have found a vulnerability in Cilium, we strongly encourage you to report it to our private security mailing list – [security@cilium.io](mailto:security@cilium.io) – first, before disclosing them in any public forums. This is a private mailing list where only members of the Cilium internal security team are subscribed to, and is treated as top priority.

CVE-2023-39347 Affected Github.com/cilium/cilium Versions

3 component(s)
Fixed Versions:
1.13.71.14.21.12.14
Product / Package Ecosystem Affected Versions Fixed Version
github.com/cilium/cilium
Go
≥ 1.13.0
< 1.13.7
1.13.7
github.com/cilium/cilium
Go
≥ 1.14.0
< 1.14.2
1.14.2
github.com/cilium/cilium
Go
< 1.12.14
1.12.14

References

Frequently Asked Questions

What is CVE-2023-39347?
CVE-2023-39347 is a security vulnerability in Github.com/cilium/cilium involving Kubernetes users may update Pod labels to bypass network policy under CWE-345: Insufficient Verification of Data Authenticity.
Which Github.com/cilium/cilium versions are affected?
Affected versions include releases prior to 1.13.7, 1.14.2, 1.12.14 across affected packages: github.com/cilium/cilium.
What version fixes CVE-2023-39347?
Upgrading to 1.13.7, 1.14.2, 1.12.14 (or the latest patched release for your respective branch) resolves the vulnerability.
Is github.com/cilium/cilium affected?
Yes, github.com/cilium/cilium is affected in releases prior to 1.13.7, 1.14.2, 1.12.14. Upgrade your dependency to 1.13.7, 1.14.2, 1.12.14 or later.
What is the CVSS score of CVE-2023-39347?
CVE-2023-39347 has a CVSS v3.1 base score of 5.4 (MODERATE) with vector string CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:L.
What CWE is associated with CVE-2023-39347?
CVE-2023-39347 is classified under CWE-345: Insufficient Verification of Data Authenticity (The product does not sufficiently verify the origin or authenticity of data, in a way that causes it to accept invalid data.).
How can I check Go dependencies for CVE-2023-39347?
Run the dependency tree command: 'inspect dependencies for github.com/cilium/cilium'. 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
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-gj2r-phwg-6rww",
  "modified" : "2023-09-27T15:42:11Z",
  "published" : "2023-09-26T18:00:22Z",
  "aliases" : [ "CVE-2023-39347" ],
  "summary" : "Kubernetes users may update Pod labels to bypass network policy",
  "details" : "### Impact\n\nAn attacker with the ability to update pod labels can cause Cilium to apply incorrect network policies.\n\nThis issue arises due to the fact that on pod update, Cilium incorrectly uses user-provided pod labels to select the policies which apply to the workload in question.\n\nThis can affect:\n\n* Cilium network policies that use the namespace, service account or cluster constructs to restrict traffic\n* Cilium clusterwide network policies that use Cilium namespace labels to select the Pod\n* Kubernetes network policies\n\nNon-existent construct names can be provided, which bypass all network policies applicable to the construct. For example, providing a pod with a non-existent namespace as the value of the `io.kubernetes.pod.namespace` label results in none of the namespaced CiliumNetworkPolicies applying to the pod in question.\n\nThis attack requires the attacker to have [Kubernetes API Server access](https://docs.cilium.io/en/latest/security/threat-model/#kubernetes-api-server-attacker), as described in the Cilium Threat Model.\n\n### Patches\n\nThis issue affects:\n\n- Cilium <= v1.14.1\n- Cilium <= v1.13.6\n- Cilium <= v1.12.13\n\nThis issue has been resolved in:\n\n- Cilium v1.14.2\n- Cilium v1.13.7\n- Cilium v1.12.14\n\n### Workarounds\n\nAn admission webhook can be used to prevent pod label updates to the `k8s:io.kubernetes.pod.namespace` and `io.cilium.k8s.policy.*` keys.\n\n### Acknowledgements\nThe Cilium community has worked together with members of Palantir and Isovalent to prepare these mitigations. Special thanks to @odinuge for reporting this issue and to @nebril for the fix.\n\n### For more information\nIf you have any questions or comments about this advisory, please reach out on [Slack](https://docs.cilium.io/en/latest/community/community/#slack).\n\nIf you think you have found a vulnerability in Cilium, we strongly encourage you to report it to our private security mailing list – [security@cilium.io](mailto:security@cilium.io) – first, before disclosing them in any public forums. This is a private mailing list where only members of the Cilium internal security team are subscribed to, and is treated as top priority.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:L"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/cilium/cilium"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "1.13.0"
      }, {
        "fixed" : "1.13.7"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 1.13.6"
    }
  }, {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/cilium/cilium"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "1.14.0"
      }, {
        "fixed" : "1.14.2"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 1.14.1"
    }
  }, {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/cilium/cilium"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.12.14"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 1.12.13"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/cilium/cilium/security/advisories/GHSA-gj2r-phwg-6rww"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2023-39347"
  }, {
    "type" : "WEB",
    "url" : "https://docs.cilium.io/en/latest/security/threat-model/#kubernetes-api-server-attacker"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/cilium/cilium"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-345" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2023-09-26T18:00:22Z",
    "nvd_published_at" : "2023-09-27T15:18:55Z"
  }
}