apache-directory-api — security advisory
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
- Products
- apache-directory-api
- Affected versions
- 1.0.0-1, 1.0.0-2, 1.0.0~M20-3, 1.0.0~M20-5, 2.1.2-1, 2.1.2-2, 2.1.2-2build1
- Fixed versions
- Not specified
- CVEs
- CVE-2026-35563
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 02:10 UTC · Revision 1
Source evidence
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
osv:UBUNTU-CVE-2026-35563
apache-directory-api
Fixed versions: Not specified
apache-directory-api
Fixed versions: Not specified
apache-directory-api
Fixed versions: Not specified
apache-directory-api
Fixed versions: Not specified
apache-directory-api
Fixed versions: Not specified
apache-directory-api
Fixed versions: Not specified
apache-directory-api
Fixed versions: Not specified
apache-directory-api
Fixed versions: Not specified
Complete source record
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"modified": "2026-10-17T12:58:13.438068748Z",
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