Unauthenticated Mailchimp metadata disclosure via open REST routes
Published Jul 23, 2026 · Updated Jul 23, 2026
Missing authorization in GutenKit 2.4.12 and earlier allows remote attackers to read private Mailchimp audience metadata through REST endpoints. The get/lists and get/interests routes use an always-true permission callback, then callbacks read the stored Mailchimp API key and return audience, field, category, interest, and subscriber-count data. Exposure requires a configured Mailchimp integration; it discloses audience configuration but does not expose the API key itself or permit changes.
Summary
What happened
Missing authorization in GutenKit 2.4.12 and earlier allows remote attackers to read private Mailchimp audience metadata through REST endpoints. The get/lists and get/interests routes use an always-true permission callback, then callbacks read the stored Mailchimp API key and return audience, field, category, interest, and subscriber-count data. Exposure requires a configured Mailchimp integration; it discloses audience configuration but does not expose the API key itself or permit changes.
The record
- CVE
- CVE-2026-15827
- Published
- Jul 23, 2026
- Updated
- Jul 23, 2026
- Vendor
- Roxnor
- Product
- GutenKit
- Classifications
- CWE-862, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 23, 2026CVE publishedPublication date reported by the CVE source.
- Jul 23, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0 <=2.4.12
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo