CVE-2026-100705: Kyverno before 1.19.1 SSRF via legacy apiCall service executor

Vulnerability summary

CVE-2026-100705 is a high (CVSS 8.3) Server-Side Request Forgery vulnerability in kyverno. EPSS estimates a 0.20% chance of exploitation in the next 30 days, higher than 9.4% of scored vulnerabilities.

Timeline

1. 26-09-2026
   PublishedVulnerability first disclosed.
2. 26-09-2026
   Last modifiedVulnerability information updated.

Description

Kyverno before 1.19.1 is vulnerable to server-side request forgery. The default egress blocklist (169.254.169.254, 169.254.169.253, metadata.google.internal, 127.0.0.0/8, ::1/128) and the scoped-token control were wired only into the new CEL http.Get/Post library and were never applied to the legacy apiCall service executor (pkg/engine/apicall/executor.go) or to the GlobalContextEntry external-API path, which handle every non-CEL context[].apiCall.service call. Because these paths use a plain net/http client with no egress filtering and no validation of the configured service URL, a ClusterPolicy or GlobalContextEntry author — or, where a deployed policy templates the service URL from the admission resource, a lower-privileged resource submitter — can cause Kyverno to issue GET/POST requests to an arbitrary host, including the cloud metadata endpoint, loopback, and any in-cluster service, reading cloud instance credentials and reaching internal endpoints with Kyverno's network position. The executor also unconditionally attaches Kyverno's projected ServiceAccount token to the attacker-chosen destination; the token is audience-scoped, limiting its replay value. Fixed in 1.19.1.

• CWE-918Server-Side Request ForgeryThe 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.