CVE-2025-54588: Envoy Race Condition Vulnerability
HIGHCVE-2025-54588 is a HIGH (CVSS 7.5) race condition vulnerability (CWE-416: Use After Free) affecting Envoy libraries in the Go ecosystem. The issue involves race condition in dynamic forward proxy leads to use-after-free and segmentation faults. Remediation is available by upgrading affected packages to version 1.35.1, 1.34.5.
CVE-2025-54588 at a Glance
Security Impact
CVSS: 7.5
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).
How to Fix CVE-2025-54588
To remediate this vulnerability, upgrade all affected Envoy dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
Upgrade github.com/envoyproxy/envoy to 1.35.1Upgrade github.com/envoyproxy/envoy to 1.34.5Run the following command in your project directory to verify that all resolved dependencies use the patched release:
inspect dependencies for github.com/envoyproxy/envoyHow to Check if You Are Affected
To determine whether your application is affected by CVE-2025-54588, inspect your project dependencies for Envoy:
inspect dependencies for github.com/envoyproxy/envoyAnalyze the terminal output to locate any version of Envoy in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.35.1), 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-416: Use After Free, where the product reuses or references memory after it has been freed. at some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer. In Envoy, 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
CVE-2025-54588 Affected Envoy Versions
2 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
github.com/envoyproxy/envoy
|
Go |
≥ 1.35.0
< 1.35.1
All 1 versions
1.35.0
|
1.35.1
|
|
github.com/envoyproxy/envoy
|
Go |
≥ 1.34.0
< 1.34.5
|
1.34.5
|
References
Frequently Asked Questions
What is CVE-2025-54588?
Which Envoy versions are affected?
What version fixes CVE-2025-54588?
Is github.com/envoyproxy/envoy affected?
What is the CVSS score of CVE-2025-54588?
What CWE is associated with CVE-2025-54588?
How can I check Go dependencies for CVE-2025-54588?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-g9vw-6pvx-7gmw",
"modified" : "2025-09-15T16:46:37Z",
"published" : "2025-09-15T16:46:37Z",
"aliases" : [ "CVE-2025-54588" ],
"summary" : "Envoy: Race condition in Dynamic Forward Proxy leads to use-after-free and segmentation faults",
"details" : "### Summary\n\nA 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.\n\n### Details\n\nThe 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:\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))",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "Go",
"name" : "github.com/envoyproxy/envoy"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "1.35.0"
}, {
"fixed" : "1.35.1"
} ]
} ],
"versions" : [ "1.35.0" ]
}, {
"package" : {
"ecosystem" : "Go",
"name" : "github.com/envoyproxy/envoy"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "1.34.0"
}, {
"fixed" : "1.34.5"
} ]
} ]
} ],
"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"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-416" ],
"severity" : "HIGH",
"github_reviewed" : true,
"github_reviewed_at" : "2025-09-15T16:46:37Z",
"nvd_published_at" : "2025-09-03T00:15:30Z"
}
}