CVE-2023-386869.3CriticalCWE-295

CVE-2023-38686: Sydent does not verify email server certificates

matrix-org · sydent

Affected: matrix-org sydent · Exploitation: unlikely (under 1%)

Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.

0.3%probability of exploitation in the next 30 days

18th percentile

050100

Higher than 18% of scored CVEs

9.3CriticalCVSS 3.1

LowMediumHighCrit.

DescriptionCVE.org

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.

Affected products1

From the CVE record. A product or version that is not listed is unknown, not unaffected.

matrix-org · sydent< 2.5.6

On the Atlas

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Exploitation: Unlikely (under 1%). EPSS under 1%, or no score yet.
CISA KEV: Not listed
Public check: No public nuclei template
Weakness: Improper Certificate Validation · Cryptography
Vendor: matrix-org
Published: August 2023
Band: Unlikely (under 1%), August 2023

CoverageNo articles yet

No CyberSIXT article names CVE-2023-38686 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.