CISA KEV catalog
Confirmed active exploitation.
Listed in CISA's catalog of Known Exploited Vulnerabilities: attackers are using it in real attacks. Patch it with priority.
- Name
- Apache Solr VelocityResponseWriter Plug-In Remote Code Execution Vulnerability
- Added to catalog
- Remediation due date (US federal)
- Required action
- Apply updates per vendor instructions.
Description
Apache Solr 5.0.0 to Apache Solr 8.3.1 are vulnerable to a Remote Code Execution through the VelocityResponseWriter. A Velocity template can be provided through Velocity templates in a configset `velocity/` directory or as a parameter. A user defined configset could contain renderable, potentially malicious, templates. Parameter provided templates are disabled by default, but can be enabled by setting `params.resource.loader.enabled` by defining a response writer with that setting set to `true`. Defining a response writer requires configuration API access. Solr 8.4 removed the params resource loader entirely, and only enables the configset-provided template rendering when the configset is `trusted` (has been uploaded by an authenticated user).
Affected products
apache: solr; oracle: primavera unifier
References10
- issues.apache.org/jira/browse/SOLR-13971 ExploitIssue TrackingPatchVendor Advisory
- issues.apache.org/jira/browse/SOLR-13971 ExploitIssue TrackingPatchVendor Advisory
- packetstormsecurity.com/files/157078/Apache-Solr-8.3.0-Velocity… ExploitThird Party AdvisoryVDB Entry
- lists.apache.org/thread.html/r5074d814d3a8c75df4b20e66bfd268ee0… ExploitMailing List
- lists.apache.org/thread.html/rf6d7ffae2b940114324e036b6394beadf… ExploitMailing List
- packetstormsecurity.com/files/157078/Apache-Solr-8.3.0-Velocity… ExploitThird Party AdvisoryVDB Entry
- lists.apache.org/thread.html/r5074d814d3a8c75df4b20e66bfd268ee0… ExploitMailing List
- lists.apache.org/thread.html/rf6d7ffae2b940114324e036b6394beadf… ExploitMailing List
- lists.apache.org/thread.html/r0b7b9d4113e6ec1ae1d3d0898c645f758… Mailing List
- lists.apache.org/thread.html/r12ab2cb15a34e49b4fecb5b2bdd7e10f3… Mailing List
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 99% percentile: 100 · as of 10 November 2026
- CWE
- CWE-74
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