Rekor affected by Server-Side Request Forgery (SSRF) via provided public key URL

Open Source Vulnerabilities GO-2026-4355

Rekor affected by Server-Side Request Forgery (SSRF) via provided public key URL in github.com/sigstore/rekor

Open Source Vulnerabilities GHSA-4c4x-jm2x-pf9j

## Summary `/api/v1/index/retrieve` supports retrieving a public key via a user-provided URL, allowing attackers to trigger SSRF to arbitrary internal services. Since the SSRF only can trigger GET requests, the request cannot mutate state. The response from the GET request is not returned to the caller so data exfiltration is not possible. A malicious actor could attempt to probe an internal network through [Blind SSRF](https://portswigger.net/web-security/ssrf/blind). ## Impact * SSRF to cloud metadata (169.254.169.254) * SSRF to internal Kubernetes APIs * SSRF to any service accessible from Fulcio's network ## Patches Upgrade to v1.5.0. Note that this is a breaking change to the search API and fully disables lookups by URL. If you require this feature, please reach out and we can discuss alternatives. ## Workarounds Disable the search endpoint with `--enable_retrieve_api=false`.

Open Source Vulnerabilities CVE-2026-24117

Rekor is a software supply chain transparency log. In versions 1.4.3 and below, attackers can trigger SSRF to arbitrary internal services because /api/v1/index/retrieve supports retrieving a public key via user-provided URL. Since the SSRF only can trigger GET requests, the request cannot mutate state. The response from the GET request is not returned to the caller so data exfiltration is not possible. A malicious actor could attempt to probe an internal network through Blind SSRF. The issue has been fixed in version 1.5.0. To workaround this issue, disable the search endpoint with --enable_retrieve_api=false.