Metacat acts as unintended proxy to backend Apache SOLR engine (CVE-2026-50022) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-50022

Metacat acts as unintended proxy to backend Apache SOLR engine

Answer in brief

CVE-2026-50022 records a Unknown severity vulnerability in Metacat acts as unintended proxy to backend Apache SOLR engine. The current sources do not mark it as known exploited. The current feed maps NCEAS/metacat (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 17, 2026Updated Sep 17, 2026Source checked Sep 17, 2026First seen by HOL Sep 17, 2026Material review Sep 17, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Not reported

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps NCEAS/metacat (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
NCEAS/metacatgeneric	< 3.4.2	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for NCEAS/metacat.
Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

Published upstream
Sep 17, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 17, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 17, 2026

Sources and claim methodology

Upstream source description

Metacat is data repository software that helps researchers preserve, share, and discover data. Prior to 3.4.2, MetacatSolrIndex.query forwards the client-controlled qt parameter through Apache SolrJ from search endpoints such as /d1/mn/v2/query/solr/ to its privileged Solr backend. An unauthenticated client can select the /admin/file handler, and SolrJ reformats the parameter into a request accepted even when handleSelect=false is configured on Solr 7.0 or later. When Solr returns the selected core configuration file, Metacat embeds the raw content in an XML processing error response, disclosing internal files such as solrconfig.xml and enabling infrastructure profiling. This issue is fixed in version 3.4.2.

Quoted source text, attributed separately from HOL analysis.