# CVE-2025-64715: cilium — Fixed in 1.18.4 🐹 🐹 Go Not in CISA KEV MEDIUM severity # CVE-2025-64715 — cilium MEDIUM [Fix: cilium/cilium@a385856](https://github.com/cilium/cilium/commit/a385856b59c8289cc7273fa3a3062bbf0ef96c97) CVE-2025-64715 is a medium-severity (CVSS 4) CWE-284 vulnerability in github.com/cilium/cilium. A fix is available for github.com/cilium/cilium — see the affected versions and patch details below. Cilium with misconfigured toGroups in policies can lead to unrestricted egress traffic Also known asBIT-cilium-2025-64715BIT-cilium-operator-2025-64715BIT-hubble-relay-2025-64715[GHSA-38pp-6gcp-rqvm](/vulnerability/GHSA-38pp-6gcp-rqvm)GO-2025-4167 Published Nov 29, 2025 Updated Oct 28, 2026 Affected 3 pkgs Patched 3 / 3 Exploits None indexed Exploitation data as of Nov 9, 2026 · OSV.dev, NVD, FIRST.org (EPSS) ## Exploitation Status ### No confirmed exploitation observed yet - CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment. Exploitation and automatability from CISA’s SSVC triage for CVE-2025-64715. ## EPSS Exploitation Probability [via FIRST.org ↗](https://www.first.org/epss/) 0.2%probability of exploitation in next 30 days Lower Risk0.00% Lower risk than most CVEs8th percentile — riskier than 8% of all scored CVEsHighest risk 0.00%0.23%0.46%0.68%0.0%0.2%May 26Sep 26Nov 26 Probability of exploitation in the next 30 days, from [FIRST.org EPSS](https://www.first.org/epss/). ## How urgent is this, really ## Where this sits among everything scored ## Real-World Exposure 3 pkgs affected 🐹`github.com/cilium/cilium`🐹`github.com/cilium/cilium`🐹`github.com/cilium/cilium` Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems. ## Description #### 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. ## Affected Packages 3 total 3 fixed Ecosystem Package Vulnerable range Fix 🐹Go `github.com/cilium/cilium` ≥ 1.18.0&&< 1.18.4 1.18.4`go get github.com/cilium/cilium@v1.18.4` 🐹Go `github.com/cilium/cilium` ≥ 1.17.0&&< 1.17.10 1.17.10`go get github.com/cilium/cilium@v1.17.10` 🐹Go `github.com/cilium/cilium` all versions 1.16.17`go get github.com/cilium/cilium@v1.16.17` ## Affected Products 1 product · 3 configurations Application `cilium`cilium ≥ 1.18.0 && < 1.18.4 range ## Detection & mitigation playbook Open-source dependency 1. ### Detect Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/cilium/cilium, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version. 2. ### Fix Update github.com/cilium/cilium to 1.18.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-64715 is resolved across your whole dependency graph. 3. ### Workarounds Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used. ## Frequently Asked Questions \### 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 an O3 Security · Impact-Aware SCA ### Is CVE-2025-64715 in your dependencies? Find it across Go, including transitive dependencies. [Scan my dependencies](/book-demo) [How O3 SCA works](/impact-aware-sca)