CVE-2026-41413: Istio SSRF Vulnerability

MODERATE
Advisory Identifier: GHSA-fgw5-hp8f-xfhc
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CVSS 5.0
CWE-918
Published
Advisory Summary

CVE-2026-41413 is a MODERATE (CVSS 5.0) ssrf vulnerability (CWE-918: Server-Side Request Forgery (SSRF)) affecting Istio libraries in the Go ecosystem. The issue involves ssrf via requestauthentication jwksuri. Remediation is available by upgrading affected packages to version 0.0.0-20260410004459-189832a289c1.

CVE-2026-41413 at a Glance

CVE Identifier CVE-2026-41413
GHSA Identifier GHSA-fgw5-hp8f-xfhc
Severity MODERATE
CVSS v3.1 Base Score 5.0
CWE Classification CWE-918: Server-Side Request Forgery (SSRF)
Affected Product Istio
Package Ecosystem Go
Published Date
Last Updated

Security Impact

CVSS: 5.0

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

Attack Vector Network (AV:N)
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 None (A:N)

How to Fix CVE-2026-41413

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

istio.io/istio fixed: 0.0.0-20260410004459-189832a289c1 
Upgrade istio.io/istio to 0.0.0-20260410004459-189832a289c1
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 istio.io/istio

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-41413, inspect your project dependencies for Istio:

inspect dependencies for istio.io/istio

Analyze the terminal output to locate any version of Istio in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.0.0-20260410004459-189832a289c1), 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-918: Server-Side Request Forgery (SSRF), where the web server receives a url or similar request from an upstream component and retrieves the contents of this url, but it does not sufficiently ensure that the request is being sent to the expected destination. In Istio, 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 When a RequestAuthentication resource is created with a jwksUri pointing to an internal service, istiod makes an unauthenticated HTTP GET request to that URL without filtering out localhost or link local ips. This can result in sensitive data being distributed to Envoy proxies via xDS configuration. Note: a partial mitigation for this was released in 1.29.1, 128.5, and 1.27.8; however, it was incomplete and missed a few codepaths. 1.29.2 and 1.28.6 contain the more robust fix. ### Patches _Has the problem been patched? What versions should users upgrade to?_ ### Workarounds Users can deploy a `ValidatingAdmissionPolicy` to prevent the creation of `RequestAuthentication` resources with suspicious jwksUri field values (e.g. localhost, 127.0.0.0/8, 169.254.0.0/16, the ipv6 variants, etc.). ### References None

CVE-2026-41413 Affected Istio Versions

1 component(s)
Fixed Versions:
0.0.0-20260410004459-189832a289c1
Product / Package Ecosystem Affected Versions Fixed Version
istio.io/istio
golang/istio.io/istio
Go
< 0.0.0-20260410004459-189832a289c1
0.0.0-20260410004459-189832a289c1

References

GitHub Advisory / Wiki ADVISORY
https://github.com/istio/istio/security/advisories/GHSA-fgw5-hp8f-xfhc
NVD — CVE-2026-41413 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-41413
Istio Source Repository REPOSITORY
https://github.com/istio/istio
Istio Release RELEASE
https://github.com/istio/istio/releases/tag/1.28.6
Istio Release RELEASE
https://github.com/istio/istio/releases/tag/1.29.2

Frequently Asked Questions

What is CVE-2026-41413?
CVE-2026-41413 is a security vulnerability in Istio involving SSRF via RequestAuthentication jwksUri under CWE-918: Server-Side Request Forgery (SSRF).
Which Istio versions are affected?
Affected versions include releases prior to 0.0.0-20260410004459-189832a289c1 across affected packages: istio.io/istio.
What version fixes CVE-2026-41413?
Upgrading to 0.0.0-20260410004459-189832a289c1 (or the latest patched release for your respective branch) resolves the vulnerability.
Is istio.io/istio affected?
Yes, istio.io/istio is affected in releases prior to 0.0.0-20260410004459-189832a289c1. Upgrade your dependency to 0.0.0-20260410004459-189832a289c1 or later.
What is the CVSS score of CVE-2026-41413?
CVE-2026-41413 has a CVSS v3.1 base score of 5.0 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N.
What CWE is associated with CVE-2026-41413?
CVE-2026-41413 is classified under CWE-918: Server-Side Request Forgery (SSRF) (The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.).
How can I check Go dependencies for CVE-2026-41413?
Run the dependency tree command: 'inspect dependencies for istio.io/istio'. 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
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-fgw5-hp8f-xfhc",
  "modified" : "2026-05-08T20:09:53Z",
  "published" : "2026-04-16T21:38:09Z",
  "aliases" : [ "CVE-2026-41413" ],
  "summary" : "Istio: SSRF via RequestAuthentication jwksUri",
  "details" : "### Impact\n\nWhen a RequestAuthentication resource is created with a jwksUri pointing to an internal service, istiod makes an unauthenticated HTTP GET request to that URL without filtering out localhost or link local ips. This can result in sensitive data being distributed to Envoy proxies via xDS configuration.\n\nNote: a partial mitigation for this was released in 1.29.1, 128.5, and 1.27.8; however, it was incomplete and missed a few codepaths. 1.29.2 and 1.28.6 contain the more robust fix.\n\n### Patches\n_Has the problem been patched? What versions should users upgrade to?_\n\n### Workarounds\n\nUsers can deploy a `ValidatingAdmissionPolicy` to prevent the creation of `RequestAuthentication` resources with suspicious jwksUri field values (e.g. localhost, 127.0.0.0/8, 169.254.0.0/16, the ipv6 variants, etc.).\n\n### References\nNone",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "istio.io/istio"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "0.0.0-20260410004459-189832a289c1"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/istio/istio/security/advisories/GHSA-fgw5-hp8f-xfhc"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-41413"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/istio/istio"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/istio/istio/releases/tag/1.28.6"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/istio/istio/releases/tag/1.29.2"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-918" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-04-16T21:38:09Z",
    "nvd_published_at" : "2026-05-07T06:16:04Z"
  }
}