Synapse is an open source Matrix homeserver implementation. Prior to 1.152.1, in federated rooms, malicious homeservers can craft room events in such a way that prevents Synapse from providing full history to paginating clients. Clients could therefore fail to display room history. This vulnerability is fixed in 1.152.1.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - Synapse is an open source Matrix homeserver implementation. Prior to 1.152.1, in federated rooms,     malicious homeservers can craft room events in such a way that prevents Synapse from providing full     history to paginating clients. Clients could therefore fail to display room history. This vulnerability is     fixed in 1.152.1. (CVE-2026-45076)

Note that Nessus relies on the presence of the package as reported by the vendor.

There are packages installed that are affected by multiple vulnerabilities referenced in the following CVEs:

  - Synapse is an open source Matrix homeserver implementation. Prior to 1.152.1, in federated rooms,
    malicious homeservers can craft room events in such a way that prevents Synapse from providing full
    history to paginating clients. Clients could therefore fail to display room history. This vulnerability is
    fixed in 1.152.1. (CVE-2026-45076)

  - Synapse is an open source Matrix homeserver implementation. Prior to 1.152.1, local authenticated users
    can cause Synapse to starve other requests of CPU and lead to other requests failing, causing other users
    to be denied service. This vulnerability is fixed in 1.152.1. (CVE-2026-45078)

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

  - Synapse is an open source Matrix homeserver implementation. Prior to 1.152.1, in federated rooms,
    malicious homeservers can craft room events in such a way that prevents Synapse from providing full
    history to paginating clients. Clients could therefore fail to display room history. This vulnerability is
    fixed in 1.152.1. (CVE-2026-45076)

ID	Name	Product	Family	Severity
318084	Linux Distros Unpatched Vulnerability : CVE-2026-45076	Nessus	Misc.	medium
442235	Alpine: synapse: security update to 1.152.1-r0	Tenable Cloud Security	Alpine Linux Local Security Checks	medium
442235	Alpine: synapse: security update to 1.152.1-r0	Tenable Self-Hosted Container Security	Alpine Linux Local Security Checks	medium
441870	SCA: security update for matrix-synapse (GHSA-6qf2-7x63-mm6v)	Tenable Cloud Security	SCA Checks	medium
441870	SCA: security update for matrix-synapse (GHSA-6qf2-7x63-mm6v)	Tenable Self-Hosted Container Security	SCA Checks	medium

Detections

Analytics

CVE-2026-45076

medium

Tenable Plugins

medium

medium

medium

medium

medium