Sydent is an identity server for the Matrix communications protocol. Prior to version 2.5.6, if configured to send emails using TLS, Sydent does not verify SMTP servers' certificates. This makes Sydent's emails vulnerable to interception via a man-in-the-middle (MITM) attack. Attackers with privileged access to the network can intercept room invitations and address confirmation emails. This is patched in Sydent 2.5.6. When patching, make sure that Sydent trusts the certificate of the server it is connecting to. This should happen automatically when using properly issued certificates. Those who use self-signed certificates should make sure to copy their Certification Authority certificate, or their self signed certificate if using only one, to the trust store of your operating system. As a workaround, one can ensure Sydent's emails fail to send by setting the configured SMTP server to a loopback or non-routable address under one's control which does not have a listening SMTP server.

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

  - Sydent is an identity server for the Matrix communications protocol. Prior to version 2.5.6, if configured     to send emails using TLS, Sydent does not verify SMTP servers' certificates. This makes Sydent's emails     vulnerable to interception via a man-in-the-middle (MITM) attack. Attackers with privileged access to the     network can intercept room invitations and address confirmation emails. This is patched in Sydent 2.5.6.
    When patching, make sure that Sydent trusts the certificate of the server it is connecting to. This should     happen automatically when using properly issued certificates. Those who use self-signed certificates     should make sure to copy their Certification Authority certificate, or their self signed certificate if     using only one, to the trust store of your operating system. As a workaround, one can ensure Sydent's     emails fail to send by setting the configured SMTP server to a loopback or non-routable address under     one's control which does not have a listening SMTP server. (CVE-2023-38686)

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

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

  - Sydent is an identity server for the Matrix communications protocol. Prior to version 2.5.6, if configured
    to send emails using TLS, Sydent does not verify SMTP servers' certificates. This makes Sydent's emails
    vulnerable to interception via a man-in-the-middle (MITM) attack. Attackers with privileged access to the
    network can intercept room invitations and address confirmation emails. This is patched in Sydent 2.5.6.
    When patching, make sure that Sydent trusts the certificate of the server it is connecting to. This should
    happen automatically when using properly issued certificates. Those who use self-signed certificates
    should make sure to copy their Certification Authority certificate, or their self signed certificate if
    using only one, to the trust store of your operating system. As a workaround, one can ensure Sydent's
    emails fail to send by setting the configured SMTP server to a loopback or non-routable address under
    one's control which does not have a listening SMTP server. (CVE-2023-38686)

ID	Name	Product	Family	Severity
253147	Linux Distros Unpatched Vulnerability : CVE-2023-38686	Nessus	Misc.	medium
417340	SCA: security update for matrix-sydent (GHSA-p6hw-wm59-3g5g)	Tenable Cloud Security	SCA Checks	medium
417340	SCA: security update for matrix-sydent (GHSA-p6hw-wm59-3g5g)	Tenable Self-Hosted Container Security	SCA Checks	medium

Detections

Analytics

CVE-2023-38686

medium

Tenable Plugins

medium

medium

medium