Description
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.
Published: 2026-01-22
Score: 5.3 Medium
EPSS: < 1% Very Low
KEV: No
Impact: Blind Server‑Side Request Forgery
Action: Apply Patch
AI Analysis

Impact

Rekor is a supply‑chain transparency log. The vulnerability allows an attacker to submit a URL to /api/v1/index/retrieve, which the service fetches via a GET request. Because the request cannot modify state and the response is not returned to the caller, the flaw cannot be used for data exfiltration, but it can be used to probe internal services through blind SSRF.

Affected Systems

Rekor versions 1.4.3 and earlier are affected, all hosted by Sigstore. The vulnerability is fixed starting with version 1.5.0.

Risk and Exploitability

The CVSS base score is 5.3, and the EPSS probability is less than 1 %. The flaw is not listed in the CISA KEV catalog. Exploitation requires network reachability to the Rekor instance and the attacker must provide a URL that the service will request; the internal network can then be enumerated via blind SSRF, with no direct data leakage.

Generated by OpenCVE AI on April 18, 2026 at 03:31 UTC.

Remediation

No vendor fix or workaround currently provided.

OpenCVE Recommended Actions

  • Upgrade Rekor to version 1.5.0 or later to correct the SSRF logic.
  • If an upgrade is not immediately possible, disable the retrieve API endpoint by running the instance with --enable_retrieve_api=false.
  • Restrict Rekor’s outbound network access to only trusted destinations to limit potential blind SSRF impact.

Generated by OpenCVE AI on April 18, 2026 at 03:31 UTC.

Tracking

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Advisories
Source ID Title
Github GHSA Github GHSA GHSA-4c4x-jm2x-pf9j Rekor affected by Server-Side Request Forgery (SSRF) via provided public key URL
History

Mon, 02 Feb 2026 15:15:00 +0000

Type Values Removed Values Added
First Time appeared Linuxfoundation
Linuxfoundation rekor
CPEs cpe:2.3:a:linuxfoundation:rekor:*:*:*:*:*:*:*:*
Vendors & Products Linuxfoundation
Linuxfoundation rekor

Wed, 28 Jan 2026 00:15:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

 threat_severity

Moderate

Fri, 23 Jan 2026 21:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Fri, 23 Jan 2026 16:45:00 +0000

Type Values Removed Values Added
First Time appeared Sigstore
Sigstore rekor
Vendors & Products Sigstore
Sigstore rekor

Thu, 22 Jan 2026 23:00:00 +0000

Type Values Removed Values Added
Description 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.
Title Rekor affected by Server-Side Request Forgery (SSRF) via provided public key URL
Weaknesses CWE-918
References
Metrics cvssV3_1

{'score': 5.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N'}

Subscriptions

Linuxfoundation Rekor
Sigstore Rekor
cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-01-23T20:14:54.031Z

Reserved: 2026-01-21T18:38:22.472Z

Link: CVE-2026-24117

cve-icon Vulnrichment

Updated: 2026-01-23T20:14:48.653Z

cve-icon NVD

Status : Analyzed

Published: 2026-01-22T22:16:21.577

Modified: 2026-02-02T15:07:44.880

Link: CVE-2026-24117

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-01-22T22:05:08Z

Links: CVE-2026-24117 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-04-18T03:45:21Z

Weaknesses