CVE-2026-55444: Goobi viewer: Solr query injection via the legacy RSS servlet q and filterQuery parameters

Vulnerability summary

CVE-2026-55444 is a medium (CVSS 5.3) Improper Input Validation vulnerability in intranda goobi-viewer-core.

Timeline

1. 23-10-2026
   PublishedVulnerability first disclosed.

Description

The Goobi viewer is a web application that allows digitised material to be displayed in a web browser. Prior to version 26.05, the legacy RSS servlet (RssResolver, GET /rss/) accepts the q and filterQuery parameters and concatenates them into Solr queries without validation. The servlet predates the REST API layer and lacks the input validation present in GET /api/v1/records/rss. q forms the main query body (wrapped only in literal parentheses); filterQuery is passed directly as a Solr fq. An unauthenticated attacker can inject Solr boolean operators to break out of the wrapping and render the trailing access-condition filter-query suffix optional, so that access-restricted records are included in the generated RSS feed. The q and filterQuery parameters are the same underlying vulnerability in the same servlet; q (the main query body) has the broader scope. This issue has been patched in version 26.05.

• CWE-20Improper Input ValidationThe product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.
• CWE-89Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')The product constructs all or part of an SQL command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended SQL command when it is sent to a downstream component. Without sufficient removal or quoting of SQL syntax in user-controllable inputs, the generated SQL query can cause those inputs to be interpreted as SQL instead of ordinary user data.
• CWE-943Improper Neutralization of Special Elements in Data Query LogicThe product generates a query intended to access or manipulate data in a data store such as a database, but it does not neutralize or incorrectly neutralizes special elements that can modify the intended logic of the query.