CVE-2025-64715: Github.com/cilium/cilium Cilium With Misconfigured ToGroups Vulnerability

MODERATE
Advisory Identifier: GHSA-38pp-6gcp-rqvm
CVSS 4.0
CWE-284
Published
Advisory Summary

CVE-2025-64715 is a MODERATE (CVSS 4.0) cilium with misconfigured togroups vulnerability (CWE-284: Improper Access Control) affecting Github.com/cilium/cilium libraries in the Go ecosystem. The issue involves cilium with misconfigured togroups in policies can lead to unrestricted egress traffic. Remediation is available by upgrading affected packages to version 1.18.4, 1.17.10, 1.16.17.

CVE-2025-64715 at a Glance

CVE Identifier CVE-2025-64715
GHSA Identifier GHSA-38pp-6gcp-rqvm
Severity MODERATE
CVSS v3.1 Base Score 4.0
CWE Classification CWE-284: Improper Access Control
Affected Product Github.com/cilium/cilium
Package Ecosystem Go
Published Date
Last Updated

Security Impact

CVSS: 4.0

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

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

How to Fix CVE-2025-64715

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: 1.18.4
Upgrade github.com/cilium/cilium to 1.18.4
github.com/cilium/cilium fixed: 1.17.10
Upgrade github.com/cilium/cilium to 1.17.10
github.com/cilium/cilium fixed: 1.16.17
Upgrade github.com/cilium/cilium to 1.16.17
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-2025-64715, 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 1.18.4), 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-284: Improper Access Control, where the product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. 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 `CiliumNetworkPolicy`s which use `egress.toGroups.aws.securityGroupsIds` to reference AWS security group IDs that do not exist or are not attached to any network interface may unintentionally allow broader outbound access than intended by the policy authors. In such cases, the toCIDRset section of the derived policy is not generated, which means outbound traffic may be permitted to more destinations than originally intended. ### Patches This issue has been patched in: * Cilium v1.18.4 * Cilium v1.17.10 * Cilium v1.16.17 ### This issue affects: - Cilium v1.18 between v1.18.0 and v1.18.3 inclusive - Cilium v1.17 between v1.17.0 and v1.17.9 inclusive - Cilium v1.16.16 and below ### Workarounds There is no workaround to this issue. ### Acknowledgements The Cilium community has worked together with members of Isovalent to prepare these mitigations. Special thanks to @SeanEmac for reporting this issue and to @fristonio for the patch. ### For more information If you think you have found a vulnerability affecting Cilium, we strongly encourage you to report it to our security mailing list at [security@cilium.io](mailto:security@cilium.io). This is a private mailing list for the Cilium security team, and your report will be treated as top priority.

CVE-2025-64715 Affected Github.com/cilium/cilium Versions

3 component(s)
Fixed Versions:
1.18.41.17.101.16.17
Product / Package Ecosystem Affected Versions Fixed Version
github.com/cilium/cilium
Go
≥ 1.18.0
< 1.18.4
1.18.4
github.com/cilium/cilium
Go
≥ 1.17.0
< 1.17.10
1.17.10
github.com/cilium/cilium
Go
< 1.16.17
1.16.17

References

Frequently Asked Questions

What is CVE-2025-64715?
CVE-2025-64715 is a security vulnerability in Github.com/cilium/cilium involving Cilium with misconfigured toGroups in policies can lead to unrestricted egress traffic under CWE-284: Improper Access Control.
Which Github.com/cilium/cilium versions are affected?
Affected versions include releases prior to 1.18.4, 1.17.10, 1.16.17 across affected packages: github.com/cilium/cilium.
What version fixes CVE-2025-64715?
Upgrading to 1.18.4, 1.17.10, 1.16.17 (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 1.18.4, 1.17.10, 1.16.17. Upgrade your dependency to 1.18.4, 1.17.10, 1.16.17 or later.
What is the CVSS score of CVE-2025-64715?
CVE-2025-64715 has a CVSS v3.1 base score of 4.0 (MODERATE) with vector string CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.
What CWE is associated with CVE-2025-64715?
CVE-2025-64715 is classified under CWE-284: Improper Access Control (The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.).
How can I check Go dependencies for CVE-2025-64715?
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-38pp-6gcp-rqvm",
  "modified" : "2026-07-02T20:21:05Z",
  "published" : "2025-12-01T18:59:54Z",
  "aliases" : [ "CVE-2025-64715" ],
  "summary" : "Cilium with misconfigured toGroups in policies can lead to unrestricted egress traffic",
  "details" : "### Impact\n\n`CiliumNetworkPolicy`s which use `egress.toGroups.aws.securityGroupsIds` to reference AWS security group IDs that do not exist or are not attached to any network interface may unintentionally allow broader outbound access than intended by the policy authors. In such cases, the toCIDRset section of the derived policy is not generated, which means outbound traffic may be permitted to more destinations than originally intended.\n\n### Patches\n\nThis issue has been patched in:\n\n* Cilium v1.18.4\n* Cilium v1.17.10\n* Cilium v1.16.17\n\n### This issue affects:\n\n- Cilium v1.18 between v1.18.0 and v1.18.3 inclusive\n- Cilium v1.17 between v1.17.0 and v1.17.9 inclusive\n- Cilium v1.16.16 and below\n\n### Workarounds\n\nThere is no workaround to this issue.\n\n### Acknowledgements\n\nThe Cilium community has worked together with members of Isovalent to prepare these mitigations. Special thanks to @SeanEmac   for reporting this issue and to @fristonio for the patch.\n\n### For more information\n\nIf you think you have found a vulnerability affecting Cilium, we strongly encourage you to report it to our security mailing list at [security@cilium.io](mailto:security@cilium.io). This is a private mailing list for the Cilium security team, and your report will be treated as top priority.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/cilium/cilium"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "1.18.0"
      }, {
        "fixed" : "1.18.4"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/cilium/cilium"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "1.17.0"
      }, {
        "fixed" : "1.17.10"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/cilium/cilium"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.16.17"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/cilium/cilium/security/advisories/GHSA-38pp-6gcp-rqvm"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-64715"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/cilium/cilium/commit/a385856b59c8289cc7273fa3a3062bbf0ef96c97"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/cilium/cilium"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/cilium/cilium/releases/tag/v1.16.17"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/cilium/cilium/releases/tag/v1.17.10"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/cilium/cilium/releases/tag/v1.18.4"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-284" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2025-12-01T18:59:54Z",
    "nvd_published_at" : "2025-11-29T01:16:01Z"
  }
}