Security readout for executives and security teams
Plain-English summary
A WordPress plugin, Kadence Blocks, can let logged-in Contributor-level users access GetResponse marketing data through the site’s stored integration credentials. The issue affects versions up to 3.6.1. Business risk is mainly confidentiality: contacts, campaigns, mailing lists, and the GetResponse API key may be exposed to lower-privileged site users.
Executive priority
Prioritize remediation for sites with marketing integrations or many non-admin content users. Treat as moderate urgency: it is not unauthenticated remote code execution, but it may expose customer or campaign data and stored API credentials.
Technical view
CVE-2026-1857 is an authenticated SSRF in the GetResponse REST API handler. Insufficient validation of the endpoint parameter in get_items(), combined with an edit_posts permission check, allows Contributor+ users to trigger server-side requests to arbitrary endpoints on the configured GetResponse API server using stored credentials.
Likely exposure
Exposure is most likely on WordPress sites running Kadence Blocks up to 3.6.1 with GetResponse integration configured and untrusted Contributor, Author, Editor, or Administrator accounts.
Exploitation context
No active exploitation is indicated by KEV, and the provided sources do not report exploitation in the wild. Exploitation requires authenticated WordPress access with Contributor-level permissions or higher, reducing broad internet-scale risk but increasing insider or compromised-account risk.
Researcher notes
The source bundle states versions up to 3.6.1 are affected. WordPress Trac references show the relevant GetResponse REST API code and a later changeset, but the bundle does not explicitly name a fixed release. Avoid assuming exploitability beyond the configured GetResponse API server.
Mitigation direction
- Update Kadence Blocks beyond version 3.6.1 if a vendor-fixed version is available.
- Review Kadence WP and Wordfence guidance for confirmed fixed versions.
- Restrict Contributor-level access to trusted users only.
- Rotate the GetResponse API key if exposure is suspected.
- Audit GetResponse contacts, campaigns, and mailing lists for unauthorized access.
Validation and detection
- Inventory WordPress sites using Kadence Blocks.
- Confirm installed Kadence Blocks versions are above 3.6.1.
- Check whether GetResponse integration is configured on each site.
- Review WordPress users with edit_posts capability.
- Inspect logs for unusual GetResponse API access from WordPress.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-918: Information exposure and cloud metadata lookup
Information exposure and SSRF weaknesses can make discovery, cloud metadata, and credential material review relevant. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCloud metadata behavior lookup
The CVE wording references SSRF or metadata access, so cloud discovery and credential material review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-1857 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 4.3 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N2.81.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
4.3MediumVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://www.wordfence.com/threat-intel/vulnerabilities/id/2ea8d38a-f5ce-40dd-a015-f56d60579e05?source=cveCVE reference
- https://plugins.trac.wordpress.org/browser/kadence-blocks/tags/3.5.32/includes/advanced-form/getresponse-rest-api.php#L77CVE reference
- https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&new=3454881%40kadence-blocks%2Ftrunk&old=3453204%40kadence-blocks%2Ftrunk&sfp_email=&sfph_mail=CVE reference
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Server-Side Request Forgery (SSRF)
Server-Side Request Forgery (SSRF) represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.