CVE-2026-1273

PostX <= 5.0.8 - Authenticated (Administrator+) Server-Side Request Forgery via REST API Endpoints

2026-03-03 12:22
Mohammad Amin Hajian (mamadrce)

Strategic Overview

Status
Patched in 5.0.9
Affected Plugin
Post Grid Gutenberg Blocks – PostX
Affected Version
<= 5.0.8
CVSS
7.2High
Weakness type
CWE-918 · Server-Side Request Forgery (SSRF)
CVE
CVE-2026-1273
View all Post Grid Gutenberg Blocks – PostX vulnerabilities

At a glance

CVE-2026-1273 is a high-severity Server-Side Request Forgery (SSRF) vulnerability in the Post Grid Gutenberg Blocks WordPress plugin, affecting versions <= 5.0.8. It carries a CVSS score of 7.2 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 5.0.9; sites on affected versions should update now. Disclosed March 2026, reported by Mohammad Amin Hajian (mamadrce).

Vulnerability Overview

The Post Grid Gutenberg Blocks for News, Magazines, Blog Websites – PostX plugin for WordPress is vulnerable to Server-Side Request Forgery in all versions up to, and including, 5.0.8 via the `/ultp/v3/starter_dummy_post/` and `/ultp/v3/starter_import_content/` REST API endpoints. This makes it possible for authenticated attackers, with Administrator-level access and above, to make web requests to arbitrary locations originating from the web application and can be used to query and modify information from internal services.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site, and no interaction from a victim user.

CWE-918: Server-Side Request Forgery (SSRF)

Reaching this weakness in Post Grid Gutenberg Blocks <= 5.0.8 takes an account at Administrator level or above. Server-side request forgery means the application fetches a URL supplied by the caller, turning the server into a proxy for requests the attacker could not make directly.

The request originates from inside the hosting network, which is how these flaws reach cloud metadata endpoints, internal admin panels and services that trust local traffic. For Post Grid Gutenberg Blocks the fix is 5.0.9: builds <= 5.0.8 are affected, anything from 5.0.9 onward is not.

Remediation

Update to version 5.0.9, or a newer patched version

How does WordSec protect against this?

An attacker needs Administrator access first, so the firewall sees the attempt as traffic from a logged-in account: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Post Grid Gutenberg Blocks 5.0.9 closes this, and updating the plugin is the step that ends it.

  • Firewall
  • Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2026-1273https://www.wordfence.com/threat-intel/vulnerabilities/id/afe6d4ac-1712-415e-9995-cb7c8fe4e1a0https://nvd.nist.gov/vuln/detail/CVE-2026-1273

Related records

Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C