Akka.NET is a .NET port of the Akka project from the Scala / Java community. In all versions of Akka.Remote from v1.2.0 to v1.5.51, TLS could be enabled via our `akka.remote.dot-netty.tcp` transport and this would correctly enforce private key validation on the server-side of inbound connections. Akka.Remote, however, never asked the outbound-connecting client to present ITS certificate - therefore it's possible for untrusted parties to connect to a private key'd Akka.NET cluster and begin communicating with it without any certificate. The issue here is that for certificate-based authentication to work properly, ensuring that all members of the Akka.Remote network are secured with the same private key, Akka.Remote needed to implement mutual TLS. This was not the case before Akka.NET v1.5.52. Those who run Akka.NET inside a private network that they fully control or who were never using TLS in the first place are now affected by the bug. However, those who use TLS to secure their networks must upgrade to Akka.NET V1.5.52 or later. One patch forces "fail fast" semantics if TLS is enabled but the private key is missing or invalid. Previous versions would only check that once connection attempts occurred. The second patch, a critical fix, enforces mutual TLS (mTLS) by default, so both parties must be keyed using the same certificate. As a workaround, avoid exposing the application publicly to avoid the vulnerability having a practical impact on one's application. However, upgrading to version 1.5.52 is still recommended by the maintainers.

There are packages installed that are affected by a vulnerability referenced in the following CVE:

  - Akka.NET is a .NET port of the Akka project from the Scala / Java community. In all versions of
    Akka.Remote from v1.2.0 to v1.5.51, TLS could be enabled via our `akka.remote.dot-netty.tcp` transport and
    this would correctly enforce private key validation on the server-side of inbound connections.
    Akka.Remote, however, never asked the outbound-connecting client to present ITS certificate - therefore
    it's possible for untrusted parties to connect to a private key'd Akka.NET cluster and begin communicating
    with it without any certificate. The issue here is that for certificate-based authentication to work
    properly, ensuring that all members of the Akka.Remote network are secured with the same private key,
    Akka.Remote needed to implement mutual TLS. This was not the case before Akka.NET v1.5.52. Those who run
    Akka.NET inside a private network that they fully control or who were never using TLS in the first place
    are now affected by the bug. However, those who use TLS to secure their networks must upgrade to Akka.NET
    V1.5.52 or later. One patch forces "fail fast" semantics if TLS is enabled but the private key is missing
    or invalid. Previous versions would only check that once connection attempts occurred. The second patch, a
    critical fix, enforces mutual TLS (mTLS) by default, so both parties must be keyed using the same
    certificate. As a workaround, avoid exposing the application publicly to avoid the vulnerability having a
    practical impact on one's application. However, upgrading to version 1.5.52 is still recommended by the
    maintainers. (CVE-2025-61778)

ID	Name	Product	Family	Type	Severity
435530	SCA: security update for Akka.Cluster, Akka.Remote (GHSA-jhpv-4q4f-43g5)	Tenable Cloud Security	SCA Checks	Local	critical
435530	SCA: security update for Akka.Cluster, Akka.Remote (GHSA-jhpv-4q4f-43g5)	Tenable Self-Hosted Container Security	SCA Checks	Local	critical

Detections

Analytics

CVE-2025-61778

critical

Tenable Plugins

critical

critical