Apache Solr VelocityResponseWriter Plug-In Remote Code Execution Vulnerability

The Apache Solr VelocityResponseWriter plug-in contains an unspecified vulnerability which can allow for remote code execution.

Published Dec 30, 2019 · Updated May 16, 2026

Why patchRisk explained in plain English

Worst-case scenarioIf unpatched

A remote attacker, with a low-privilege account, can achieve full data confidentiality loss, arbitrary modification of data, complete denial of service or system unavailability. Federal agencies are required to remediate by 2022-05-03 under CISA BOD 22-01.

How the attack worksNo clicks needed

This is a Software Vulnerability (CWE-74) (CWE-74) vulnerability in Apache Solr. Exploitation requires remote network access, higher attack complexity, a low-privilege authenticated account, and no user interaction required.

Am I affected?Quick check

Probably yes if any of these apply:

●IT Security

●Running solr: 5.0.0 ≤ v < 7.7.3, 8.0.0 ≤ v < 8.4.0; primavera unifier: 17.7 ≤ v ≤ 17.12, 16.1, 16.2, 18.8, 19.12

Real-world incidentsWhat we've seen

Active exploitation documented in the wild. Threat-research write-up: http://packetstormsecurity.com/files/157078/Apache-Solr-8.3.0-Velocity-Template-Remote-Code-Execution.html

How to patch

Manual remediation steps

Apply the Vendor Patch

This vulnerability is in the CISA Known Exploited Vulnerabilities catalog — apply the vendor's security update as soon as possible.

CISA required action: Apply updates per vendor instructions.

References

Vendor advisory: https://issues.apache.org/jira/browse/SOLR-13971

NVD entry: https://nvd.nist.gov/vuln/detail/CVE-2019-17558

CISA KEV: https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2019-17558

PowerShell automationComing soon

No tested PowerShell script for this entry yet. We’re prioritising automation based on user demand.

References

↗ CVE-2019-17558 ↗ NVD ↗ Vendor Advisory