GHSA-FGW5-HP8F-XFHC
Vulnerability from github – Published: 2026-04-16 21:38 – Updated: 2026-04-16 21:38Impact
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
{
"affected": [
{
"package": {
"ecosystem": "Go",
"name": "istio.io/istio"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "0.0.0-20260410004459-189832a289c1"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [],
"database_specific": {
"cwe_ids": [
"CWE-918"
],
"github_reviewed": true,
"github_reviewed_at": "2026-04-16T21:38:09Z",
"nvd_published_at": null,
"severity": "MODERATE"
},
"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",
"id": "GHSA-fgw5-hp8f-xfhc",
"modified": "2026-04-16T21:38:09Z",
"published": "2026-04-16T21:38:09Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/istio/istio/security/advisories/GHSA-fgw5-hp8f-xfhc"
},
{
"type": "PACKAGE",
"url": "https://github.com/istio/istio"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N",
"type": "CVSS_V3"
}
],
"summary": "Istio: SSRF via RequestAuthentication jwksUri"
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.