CVE-2025-55715: Otter Gutenberg Block Info Disclosure

CVE-2025-55715 Overview

CVE-2025-55715 is a sensitive data exposure vulnerability in the Themeisle Otter - Gutenberg Blocks plugin for WordPress. The flaw allows unauthenticated remote attackers to retrieve embedded sensitive information from affected sites over the network. The issue is classified under [CWE-201]: Insertion of Sensitive Information Into Sent Data, and affects all plugin versions up to and including 3.1.0. Exploitation requires no privileges and no user interaction, making any public-facing WordPress site running a vulnerable Otter Blocks installation reachable to opportunistic scanning.

Critical Impact
Unauthenticated attackers can retrieve sensitive data embedded in Otter Blocks responses without privileges or user interaction, directly impacting confidentiality of WordPress site data.

Affected Products

Themeisle Otter - Gutenberg Blocks plugin for WordPress, versions up to and including 3.1.0
WordPress sites with the otter-blocks plugin installed and activated
All hosting environments running the affected plugin version, regardless of WordPress core version

Discovery Timeline

2025-08-20 - CVE-2025-55715 published to NVD
2026-04-23 - Last updated in NVD database

Technical Details for CVE-2025-55715

Vulnerability Analysis

The vulnerability resides in the Otter Blocks plugin, a Gutenberg block library that extends the WordPress block editor with additional design components. The plugin includes sensitive information in data sent to clients without proper access controls or filtering. An unauthenticated attacker can request the affected endpoint or rendered output and retrieve embedded data that should remain server-side or restricted to authorized users.

The integrity and availability of the host are not directly affected. However, exposed data can include configuration values, credentials, or content that supports follow-on attacks against the WordPress instance or connected services.

Root Cause

The root cause is improper handling of sensitive information during response generation in the otter-blocks plugin. Code paths that render or serialize block data embed values that should be excluded from output sent to unauthenticated requesters. This maps to [CWE-201], where sensitive data is inserted into outbound communication that can be observed by unintended parties.

Attack Vector

The attack vector is network-based. An attacker sends crafted HTTP requests to a WordPress site running Otter Blocks <= 3.1.0 and parses the responses to extract embedded sensitive content. No authentication, privileges, or user interaction are required. Automated scanners can identify vulnerable installations through plugin fingerprinting and harvest exposed data at scale.

Refer to the Patchstack Vulnerability Report for additional technical context.

Detection Methods for CVE-2025-55715

Indicators of Compromise

Unusual unauthenticated HTTP GET requests targeting WordPress REST API endpoints registered by the otter-blocks plugin
Repeated scraping of pages containing Otter blocks from a single source IP or distributed scanner infrastructure
Outbound responses from /wp-json/ routes that include unexpected configuration or credential-like fields

Detection Strategies

Inventory all WordPress installations and identify sites where otter-blocks is installed at version 3.1.0 or earlier
Inspect web server access logs for anomalous access patterns to plugin-specific REST routes and rendered block content
Use web application firewall (WAF) telemetry to flag unauthenticated requests retrieving large or sensitive response payloads from plugin endpoints

Monitoring Recommendations

Forward WordPress and reverse-proxy logs into a centralized SIEM and alert on spikes in anonymous requests to plugin endpoints
Monitor plugin version metadata across managed WordPress fleets to detect installations still running vulnerable releases
Track threat intelligence feeds and the Patchstack Vulnerability Report for updated indicators

How to Mitigate CVE-2025-55715

Immediate Actions Required

Upgrade the Otter - Gutenberg Blocks plugin to a version newer than 3.1.0 on every affected WordPress site
Audit pages and REST API responses generated by Otter Blocks for any sensitive data that may have already been exposed
Rotate any credentials, API keys, or tokens that could have been embedded in block content or plugin output

Patch Information

The vendor has released a fixed version of the otter-blocks plugin addressing this issue. Site administrators should update through the WordPress plugin manager or via WP-CLI. Consult the Patchstack Vulnerability Report for the specific patched release.

Workarounds

Temporarily deactivate the otter-blocks plugin until patching is complete on production sites
Restrict access to WordPress REST API endpoints through a WAF rule set that blocks unauthenticated scraping of plugin routes
Remove any sensitive content stored in Otter blocks and migrate it to access-controlled locations

bash

# Update Otter Blocks via WP-CLI on the affected site
wp plugin update otter-blocks
wp plugin get otter-blocks --field=version