CVE-2023-50386 — solr-core
HIGHCVE-2023-50386 is a high-severity (CVSS 8.8) Unrestricted File Upload vulnerability in org.apache.solr:solr-core. 4 public exploit references exist, so weaponization risk is real. A fix is available for org.apache.solr:solr-core — see the affected versions and patch details below.
Apache Solr: Backup/Restore APIs allow for deployment of executables in malicious ConfigSets
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA’s SSVC triage for CVE-2023-50386.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2023-50386 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE sits: patch-first territory.
Where this sits among everything scored
Of 377,166 CVEs with a current EPSS score, this one falls in the 50–90% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
org.apache.solr:solr-core☕org.apache.solr:solr-coreReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
Improper Control of Dynamically-Managed Code Resources, Unrestricted Upload of File with Dangerous Type, Inclusion of Functionality from Untrusted Control Sphere vulnerability in Apache Solr.This issue affects Apache Solr: from 6.0.0 through 8.11.2, from 9.0.0 before 9.4.1.
In the affected versions, Solr ConfigSets accepted Java jar and class files to be uploaded through the ConfigSets API. When backing up Solr Collections, these configSet files would be saved to disk when using the LocalFileSystemRepository (the default for backups). If the backup was saved to a directory that Solr uses in its ClassPath/ClassLoaders, then the jar and class files would be available to use with any ConfigSet, trusted or untrusted.
When Solr is run in a secure way (Authorization enabled), as is strongly suggested, this vulnerability is limited to extending the Backup permissions with the ability to add libraries. Users are recommended to upgrade to version 8.11.3 or 9.4.1, which fix the issue. In these versions, the following protections have been added:
- Users are no longer able to upload files to a configSet that could be executed via a Java ClassLoader.
- The Backup API restricts saving backups to directories that are used in the ClassLoader.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.apache.solr:solr-core | ≥ 6.0.0&&< 8.11.3 | 8.11.3org.apache.solr:solr-core:8.11.3 |
| ☕Maven | org.apache.solr:solr-core | ≥ 9.0.0&&< 9.4.1 | 9.4.1org.apache.solr:solr-core:9.4.1 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.solr:solr-core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.apache.solr:solr-core to 8.11.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-50386 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2023-50386 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2023-50386. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2023-50386 in your dependencies?
O3 Security finds CVE-2023-50386 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.