High
apache-directory-api — security advisory
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.
- 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-2026-102731
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 02:53 UTC · Revision 1
Source evidence
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.
osv:UBUNTU-CVE-2026-102731
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": "2026-10-17T12:59:45.787286776Z",
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"https://www.openwall.com/lists/oss-security/2026/10/02/3",
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