CVE-2026-54775
CoreWCF: Kafka consume pump halts permanently on a Kafka tombstone (null-value record), causing persistent endpoint denial of service.
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
CoreWCF: Kafka consume pump halts permanently on a Kafka tombstone (null-value record), causing persistent endpoint denial of service.
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.
- Record
CVE-2026-54775- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-248, CWE-754, CWE-755
- Updated
- 2026-11-02
EUVDEUVD-2026-42466
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.
- Record
EUVD-2026-42466- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-m744-jhq9-ppw6
CoreWCF: Kafka consume pump halts permanently on a Kafka tombstone (null-value record), causing persistent endpoint denial of service.
Impact
A CoreWCF service is running and listening on a Kafka topic receiving a null-value record will stop processing new records from that topic.
Preconditions
The attacker has produce/write permission on a topic that CoreWCF is consuming from. If the broker permits anonymous publishes, no authentication is required.
Patches
Fixed in CoreWCF v1.8.1 and v1.9.1
Workarounds
Only allow authenticated writes to a topic
- Record
GHSA-m744-jhq9-ppw6- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-248, CWE-754, CWE-755
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-54775- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-248, CWE-754, CWE-755
- Updated
- 2026-11-02
OSV
CoreWCF: Kafka consume pump halts permanently on a Kafka tombstone (null-value record), causing persistent endpoint denial of service.
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.
- Record
CVE-2026-54775- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-248, CWE-754, CWE-755
- Updated
- 2026-11-02
OSVGHSA-m744-jhq9-ppw6
CoreWCF: Kafka consume pump halts permanently on a Kafka tombstone (null-value record), causing persistent endpoint denial of service.
Impact
A CoreWCF service is running and listening on a Kafka topic receiving a null-value record will stop processing new records from that topic.
Preconditions
The attacker has produce/write permission on a topic that CoreWCF is consuming from. If the broker permits anonymous publishes, no authentication is required.
Patches
Fixed in CoreWCF v1.8.1 and v1.9.1
Workarounds
Only allow authenticated writes to a topic
- Record
GHSA-m744-jhq9-ppw6- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-248, CWE-754, CWE-755
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
CoreWCF.KafkaNuGet |
before 1.8.1 | 1.8.1 |
CoreWCF.KafkaNuGet |
1.9.0 up to 1.9.1 | 1.9.1 |
CoreWCF.KafkaNuGet |
before 1.8.1, plus listed versions 1.4.01.4.11.4.21.5.01.5.0-preview1 Show 5 moreShow less1.5.11.5.21.6.01.7.01.8.0 |
1.8.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-54775 is a medium vulnerability (CVSS 6.5) in Corewcf, published June 19, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.60%, the 48th percentile. Fixed in CoreWCF.Kafka 1.8.1.
References
github.com/CoreWCF/CoreWCF/security/advisories/GHSA-m744-jhq9-ppw6