CVE-2026-103345 Overview
CVE-2026-103345 is a sensitive data exposure vulnerability in the Pie Register plugin for WordPress, developed by Shamim Rajani. The flaw affects all versions of the plugin from the initial release through 3.8.4.13. It is classified under [CWE-201] (Insertion of Sensitive Information Into Sent Data), meaning the plugin embeds confidential information into responses accessible to unauthorized actors.
Unauthenticated attackers can retrieve this embedded sensitive data over the network without any user interaction. The vulnerability was published to the National Vulnerability Database (NVD) on October 1, 2026.
Critical Impact
Remote, unauthenticated attackers can retrieve sensitive information embedded in plugin-generated responses, enabling reconnaissance or follow-on account compromise against WordPress sites using Pie Register.
Affected Products
- Pie Register plugin for WordPress (pie-register)
- All versions from initial release through 3.8.4.13
- WordPress sites with the plugin active for user registration workflows
Discovery Timeline
- 2026-10-01 - CVE-2026-103345 published to NVD
- 2026-10-01 - Last updated in NVD database
Technical Details for CVE-2026-103345
Vulnerability Analysis
The Pie Register plugin provides custom user registration, login, and profile management for WordPress sites. The vulnerability stems from the plugin embedding sensitive information into data that is sent to clients during normal operation. Because the attack vector is network-based and requires no authentication or user interaction, any remote actor who can reach the WordPress site can trigger the data exposure.
The weakness falls under [CWE-201], a class of defects where information intended to remain private is inadvertently included in transmitted output. Examples include debug fields in JSON responses, hidden form inputs, metadata in rendered pages, or verbose API payloads. The impact is limited to confidentiality; integrity and availability are not affected.
Root Cause
The root cause is improper separation between internal data structures and the subset of data intended for client-facing responses. The plugin's response-building logic in versions up to and including 3.8.4.13 serializes fields that should remain server-side, exposing them to unauthorized viewers. Full technical specifics are available in the Patchstack CVE Analysis.
Attack Vector
An attacker sends crafted HTTP requests to a WordPress endpoint exposed by the Pie Register plugin. The server returns responses that contain the embedded sensitive data. No credentials, cookies, or social engineering are required. The exposed information can support reconnaissance, user enumeration, or chaining with other weaknesses in the WordPress stack. The EPSS score at publication was 0.197%, reflecting low observed exploitation activity to date.
No verified exploit code is publicly available. Readers should consult the Patchstack advisory for additional technical context.
Detection Methods for CVE-2026-103345
Indicators of Compromise
- Repeated unauthenticated requests to Pie Register endpoints under /wp-json/, wp-admin/admin-ajax.php, or plugin-specific URLs
- HTTP responses from Pie Register endpoints containing unexpected user fields, tokens, or metadata not needed by the client
- Anomalous spikes in outbound response sizes from pages where the plugin renders registration or profile data
Detection Strategies
- Inventory WordPress deployments and flag any site running pie-register at version 3.8.4.13 or earlier
- Inspect HTTP responses from registration, login, and profile endpoints for sensitive fields such as email addresses, hashed credentials, user IDs, or internal identifiers
- Correlate web server access logs with user enumeration patterns targeting Pie Register routes
Monitoring Recommendations
- Enable web application firewall (WAF) logging for all requests to Pie Register endpoints and alert on high request volume from single sources
- Monitor WordPress plugin inventory continuously and alert when vulnerable versions are detected
- Review the Patchstack CVE Analysis for any updated indicators as the advisory evolves
How to Mitigate CVE-2026-103345
Immediate Actions Required
- Identify all WordPress sites running the Pie Register plugin and determine installed versions
- Upgrade pie-register to a version later than 3.8.4.13 once the vendor publishes a fixed release
- Restrict access to registration and profile endpoints to trusted networks where feasible until a patch is applied
Patch Information
The vulnerability affects Pie Register versions through 3.8.4.13. Administrators should consult the Patchstack advisory and the WordPress plugin repository for the fixed release and upgrade immediately once available.
Workarounds
- Deactivate the Pie Register plugin on sites that do not require custom registration functionality
- Place a WAF rule in front of Pie Register endpoints to strip or block responses containing sensitive fields
- Enforce rate limiting on registration and profile endpoints to slow automated data harvesting
# Example WordPress CLI check for installed Pie Register version
wp plugin get pie-register --field=version
# Upgrade once a fixed release is published
wp plugin update pie-register
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
