ghsa-g9vw-6pvx-7gmw
Vulnerability from github
Summary
A use-after-free (UAF) vulnerability in Envoy's DNS cache causes abnormal process termination. Envoy may reallocate memory when processing a pending DNS resolution, causing list iterator to reference freed memory.
Details
The vulnerability exists in Envoy's Dynamic Forward Proxy implementation starting from version v1.34.0. The issue occurs when a completion callback for a DNS resolution triggers new DNS resolutions or removes existing pending resolutions. This condition may occur in the following configuration:
- Dynamic Forwarding Filter is enabled.
envoy.reloadable_features.dfp_cluster_resolves_hosts
runtime flag is enabled.- The Host header is modified between the Dynamic Forwarding Filter and Router filters.
Impact
Denial of service due to abnormal process termination.
Attack vector(s)
Request to Envoy configured as indicated above.
Patches
Users should upgrade to v1.35.1 or v1.34.5.
Workaround
Set the envoy.reloadable_features.dfp_cluster_resolves_hosts
runtime flag to false
.
Detection
Abnormal process termination with the Envoy::Event::DispatcherImpl::runPostCallbacks()
frame in the call stack.
Credits
Rohit Agrawal (agrawroh) (rohit.agrawal@databricks.com)
{ "affected": [ { "package": { "ecosystem": "Go", "name": "github.com/envoyproxy/envoy" }, "ranges": [ { "events": [ { "introduced": "1.35.0" }, { "fixed": "1.35.1" } ], "type": "ECOSYSTEM" } ], "versions": [ "1.35.0" ] }, { "package": { "ecosystem": "Go", "name": "github.com/envoyproxy/envoy" }, "ranges": [ { "events": [ { "introduced": "1.34.0" }, { "fixed": "1.34.5" } ], "type": "ECOSYSTEM" } ] } ], "aliases": [ "CVE-2025-54588" ], "database_specific": { "cwe_ids": [ "CWE-416" ], "github_reviewed": true, "github_reviewed_at": "2025-09-15T16:46:37Z", "nvd_published_at": "2025-09-03T00:15:30Z", "severity": "HIGH" }, "details": "### Summary\n\nA use-after-free (UAF) vulnerability in Envoy\u0027s DNS cache causes abnormal process termination. Envoy may reallocate memory when processing a pending DNS resolution, causing list iterator to reference freed memory.\n\n### Details\n\nThe vulnerability exists in Envoy\u0027s Dynamic Forward Proxy implementation starting from version v1.34.0. The issue occurs when a completion callback for a DNS resolution triggers new DNS resolutions or removes existing pending resolutions. This condition may occur in the following configuration:\n\n1. Dynamic Forwarding Filter is enabled.\n2. `envoy.reloadable_features.dfp_cluster_resolves_hosts` runtime flag is enabled.\n3. The Host header is modified between the Dynamic Forwarding Filter and Router filters.\n\n### Impact\n\nDenial of service due to abnormal process termination.\n\n### Attack vector(s)\nRequest to Envoy configured as indicated above.\n\n### Patches\nUsers should upgrade to v1.35.1 or v1.34.5. \n\n### Workaround\nSet the `envoy.reloadable_features.dfp_cluster_resolves_hosts` runtime flag to `false`.\n\n### Detection\nAbnormal process termination with the `Envoy::Event::DispatcherImpl::runPostCallbacks()` frame in the call stack.\n\n### Credits\nRohit Agrawal ([agrawroh](https://github.com/agrawroh)) ([rohit.agrawal@databricks.com](mailto:rohit.agrawal@databricks.com))", "id": "GHSA-g9vw-6pvx-7gmw", "modified": "2025-09-15T16:46:37Z", "published": "2025-09-15T16:46:37Z", "references": [ { "type": "WEB", "url": "https://github.com/envoyproxy/envoy/security/advisories/GHSA-g9vw-6pvx-7gmw" }, { "type": "ADVISORY", "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-54588" }, { "type": "PACKAGE", "url": "https://github.com/envoyproxy/envoy" }, { "type": "WEB", "url": "https://github.com/envoyproxy/envoy/releases/tag/v1.34.5" }, { "type": "WEB", "url": "https://github.com/envoyproxy/envoy/releases/tag/v1.35.1" } ], "schema_version": "1.4.0", "severity": [ { "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "type": "CVSS_V3" } ], "summary": "Envoy: Race condition in Dynamic Forward Proxy leads to use-after-free and segmentation faults" }
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.