CVE-2026-54775
MEDIUMCoreWCF: Kafka consume pump halts permanently on a Kafka tombstone (null-value record), causing persistent endpoint denial of service.
Blast Radius
CoreWCF.Kafka.NETCoreWCF.KafkaReal-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
CoreWCF is a port of the service side of Windows Communication Foundation (WCF) to .NET Core. Prior to 1.8.1 and 1.9.1, a CoreWCF service listening on a Kafka topic stops processing new records from that topic when KafkaTransportPump receives a null-value tombstone record, causing a persistent endpoint denial of service for attackers with produce permission. This issue is fixed in versions 1.8.1 and 1.9.1.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| .NETNuGet | CoreWCF.Kafka | all versions | 1.8.1 |
| .NETNuGet | CoreWCF.Kafka | ≥ 1.9.0&&< 1.9.1 | 1.9.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for CoreWCF.Kafka. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update CoreWCF.Kafka to 1.8.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-54775 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 pinpoints whether CVE-2026-54775 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-54775. 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-2026-54775 in your dependencies?
O3 detects CVE-2026-54775 across NuGet dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.