CVE-2024-43383 — Lucene.Net.Replicator
HIGHCVE-2024-43383 is a high-severity (CVSS 8) Deserialization of Untrusted Data vulnerability in Lucene.Net.Replicator. A fix is available for Lucene.Net.Replicator — see the affected versions and patch details below.
Apache Lucene.Net.Replicator: Remote Code Execution in Lucene.Net.Replicator
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2024-43383.
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-2024-43383 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,333 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
Lucene.Net.ReplicatorReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects NuGet packages — download data is not available via public APIs for these ecosystems.
Description
Deserialization of Untrusted Data vulnerability in Apache Lucene.Net.Replicator.
This issue affects Apache Lucene.NET's Replicator library: from 4.8.0-beta00005 through 4.8.0-beta00016.
An attacker that can intercept traffic between a replication client and server, or control the target replication node URL, can provide a specially-crafted JSON response that is deserialized as an attacker-provided exception type. This can result in remote code execution or other potential unauthorized access.
Users are recommended to upgrade to version 4.8.0-beta00017, which fixes the issue.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| .NETNuGet | Lucene.Net.Replicator | ≥ 4.8.0-beta00005&&< 4.8.0-beta00017 | 4.8.0-beta00017dotnet add package Lucene.Net.Replicator --version 4.8.0-beta00017 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for Lucene.Net.Replicator, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update Lucene.Net.Replicator to 4.8.0-beta00017 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-43383 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-2024-43383 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2024-43383. 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-2024-43383 in your dependencies?
O3 Security finds CVE-2024-43383 across NuGet dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.