CVE-2026-6394
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedThe Nexa Blocks – Gutenberg Blocks, Page Builder for Gutenberg Editor & FSE plugin for WordPress is vulnerable to Server-Side Request Forgery (SSRF) in versions up to and including 1.1.1. This is due to the import_demo() function accepting a user-supplied URL in the demo_json_file POST parameter and passing it directly to wp_remote_get() without any URL validation or restriction against internal or private network destinations. The nexa_blocks_nonce required for the AJAX action is publicly exposed in the HTML source of any frontend page where the plugin is active via wp_localize_script on the enqueue_block_assets hook, effectively making the nonce available to all visitors and bypassing any intended authentication barrier. This makes it possible for unauthenticated attackers to make server-side HTTP requests to arbitrary internal or external destinations, potentially exposing internal services, cloud metadata endpoints such as the AWS instance metadata service, localhost services, and other resources not intended to be publicly accessible. A secondary SSRF vector also exists whereby image URLs extracted from the attacker-controlled JSON response are subsequently fetched via a second wp_remote_get() call, allowing chained exploitation through a crafted JSON payload.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceThe Nexa Blocks plugin up to 1.1.1 contains an SSRF vulnerability in its import_demo() function. The function accepts a user-supplied URL via the demo_json_file POST parameter and passes it directly to wp_remote_get() without any validation. The required AJAX nonce is publicly exposed in frontend HTML source via wp_localize_script, allowing unauthenticated attackers to exploit this. A secondary SSRF vector exists through image URLs extracted from attacker-controlled JSON responses.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- High
- Privileges
- None
- User interaction
- None
- Scope
- Changed
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Confirm Nexa Blocks plugin is installedNavigate to WordPress admin dashboard > Plugins, or inspect the wp-content/plugins/nexa-blocks directory for version informationAffected if Nexa Blocks plugin is present and the version is 1.1.1 or lower
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Verify the vulnerable AJAX action existsSearch the plugin source code for the import_demo function definition, or grep for 'wp_ajax_nopriv_import_demo' or 'wp_ajax_import_demo' in the plugin filesAffected if The import_demo AJAX action is registered and accessible to unauthenticated users (wp_ajax_nopriv_)
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Check for absence of URL validation in import_demoReview the import_demo function code in the plugin files to confirm that the demo_json_file parameter is passed directly to wp_remote_get() without validationAffected if The code passes user input directly to wp_remote_get() without sanitization or allowlist checks
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Confirm nonce exposure via wp_localize_scriptView the HTML source of any frontend page, or search plugin files for wp_localize_script calls containing 'nexa_blocks_nonce'Affected if The security nonce is exposed in JavaScript variables accessible to any page visitor, enabling unauthenticated exploitation
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Verify WordPress HTTP requests are enabledTest that wp_remote_get() functions work from the server, or check that WordPress HTTP API is not disabled via DISALLOW_FILE_MODS or similar constantsAffected if The server can make outbound HTTP requests (a prerequisite for the SSRF to function)
A user is affected if they have Nexa Blocks plugin version 1.1.1 or lower installed, the plugin exposes the import_demo AJAX action to unauthenticated users, and the server can make outbound HTTP requests.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
From vendor dataUpdate to a patched version when available. Until then, consider restricting network access from the web server and monitor for suspicious requests to the import_demo AJAX action.
- Consultation3.0 h
- Implementation5.0 h
- Testing3.0 h
- Review / QA2.0 h
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Free · runs locallyCheck whether your project pulls in CVE-2026-6394 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-6394 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
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