CVE-2026-103877
Apache Directory LDAP API: Unsafe loading of Java code from LDAP schema elements
Apache Software Foundation Apache Directory LDAP API
CVSS
9.8CriticalExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.57%Chance of exploitation activity in the next 30 days, higher than 46% of CVEs. Scored 23 Oct 2026FIRST EPSS
What fixes it
- 2.1.9Apache Directory LDAP APICVE List
A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.
Description
Deserialization of Untrusted Data vulnerability in Apache Directory LDAP API.
A rogue/compromised LDAP server (or pre-TLS MITM) can answer a client's loadSchema() subschema search with a schema object that contains a serialized Java class, allowing some potential RCE.
This issue affects Apache Directory LDAP API: from 2.1.0 before 2.1.9.
Users are recommended to upgrade to version 2.1.9, which fixes the issue.
Text from CVE List
Affected versions 1
- Apache Directory LDAP APIaffected: 2.1.0 before 2.1.9CVE List