Vulnerability Description
Memory allocation with excessive size value vulnerability in Apache Directory LDAP API. A malicious peer (or a MITM) can send a small BER-encoded response causing a large memory allocation before any data is received. This can lead to an OutOfMemoryError and denial of service. The client JVM OOMs (OutOfMemoryError bypasses the DecoderException handlers) or pins the large allocation per connection while the attacker stalls. A handful of connections exhausts any heap. The same bytes from an unauthenticated pre-bind client hit any embedding server that did not set MAX_PDU_SIZE_ATTR. This issue affects Apache Directory LDAP API: from 1.2.0 before 1.2.9. Users are recommended to upgrade to version 1.2.9, which fixes the issue.
Related Weaknesses (CWE)
References
- https://lists.apache.org/thread.html/b8kg8881pc0v8lp59w0fcfrs69wjbqvd
- http://www.openwall.com/lists/oss-security/2026/10/02/3
FAQ
What is CVE-2026-102731?
CVE-2026-102731 is a documented vulnerability. Memory allocation with excessive size value vulnerability in Apache Directory LDAP API. A malicious peer (or a MITM) can send a small BER-encoded response causing a large memory allocation before a...
How severe is CVE-2026-102731?
CVSS scoring is not yet available for CVE-2026-102731. Check NVD for updates.
Is there a patch for CVE-2026-102731?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.