It was identified that the LDAP client implementation in version 2.1.7 does not verify if the server certificate matches the intended LDAP hostname. While the underlying code validates the certificate chain against a trusted authority, the absence of endpoint identification allows a valid certificate issued for an entirely unrelated host to be improperly accepted. This oversight leaves the connection highly vulnerable to server impersonation and complete connection compromise. The root cause of this vulnerability lies in the incomplete TLS server identity verification within the LDAP client implementation. The attacker requires MITM capability on the network to exploit this vulnerability. This attacker must be able to present a certificate trusted by the client's configured trust store. The hostname verification has been enforced in the new version of the LDAP API

The version of FreeBSD installed on the remote host is prior to tested version. It is, therefore, affected by multiple vulnerabilities as referenced in the 2eb1927c-a57b-11f1-9b1f-3c7c3fba4204 advisory.

    The Keycloak Team reports:

Tenable has extracted the preceding description block directly from the FreeBSD security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

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

  - It was identified that the LDAP client implementation in version 2.1.7 does not verify if the server     certificate matches the intended LDAP hostname. While the underlying code validates the certificate chain     against a trusted authority, the absence of endpoint identification allows a valid certificate issued for     an entirely unrelated host to be improperly accepted. This oversight leaves the connection highly     vulnerable to server impersonation and complete connection compromise. The root cause of this     vulnerability lies in the incomplete TLS server identity verification within the LDAP client     implementation. The attacker requires MITM capability on the network to exploit this vulnerability. This     attacker must be able to present a certificate trusted by the client's configured trust store. The     hostname verification has been enforced in the new version of the LDAP API (CVE-2026-35563)

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

ID	Name	Product	Family	Type	Severity
342210	FreeBSD : Keycloak -- multiple vulnerabilities (2eb1927c-a57b-11f1-9b1f-3c7c3fba4204)	Nessus	FreeBSD Local Security Checks	Local	high
318281	Linux Distros Unpatched Vulnerability : CVE-2026-35563	Nessus	Misc.	Local	high

Detections

Analytics

CVE-2026-35563

high

Tenable Plugins

high

high