High 7.5Published Oct 2, 2026

CVE-2026-102731Apache Directory LDAP API: Denial of service via excessive memory allocation in BER decode

Updated under an hour ago (2026-10-19 07:23 UTC)

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It affects Apache Software Foundation Apache Directory LDAP API. Add what you run to find out whether that includes you.

EPSS puts the chance of exploitation in the next 30 days at 0.43%, higher than 36% of scored CVEs.

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Every CVE for Apache Software Foundation Apache Directory LDAP API

Exploited in the last 30 days

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.

CVSS: 7.5 HIGH (v3.1, CISA ADP)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-789
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): 0.43% (percentile 36)
Assigned by: apache
NVD analysis: Deferred
Record last updated: Oct 5, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Apache Software Foundation Apache Directory LDAP API apache_software_foundation:apache_directory_ldap_api (from the name)	from 1.2.0 before 1.2.9	CNA record

References

https://lists.apache.org/thread.html/b8kg8881pc0v8lp59w0fcfrs69wjbqvdvendor-advisory
http://www.openwall.com/lists/oss-security/2026/10/02/3

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.