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GHSA-H24G-PJPF-8F2M

Vulnerability from github – Published: 2026-10-02 12:31 – Updated: 2026-10-02 12:31

Details

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.

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  "affected": [],
  "aliases": [
    "CVE-2026-102731"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-789"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-10-02T10:17:04Z",
    "severity": null
  },
  "details": "Memory allocation with excessive size value vulnerability in Apache Directory LDAP API.\n\n\n\nA 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.\n\n\n\nThe client JVM OOMs (OutOfMemoryError bypasses the DecoderException handlers) or pins the large allocation per connection while the attacker stalls.\n\n\n\nA 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.\n\n\n\nThis issue affects Apache Directory LDAP API: from 1.2.0 before 1.2.9.\n\n\n\nUsers are recommended to upgrade to version 1.2.9, which fixes the issue.",
  "id": "GHSA-h24g-pjpf-8f2m",
  "modified": "2026-10-02T12:31:09Z",
  "published": "2026-10-02T12:31:09Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-102731"
    },
    {
      "type": "WEB",
      "url": "https://lists.apache.org/thread.html/b8kg8881pc0v8lp59w0fcfrs69wjbqvd"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

CVE-2026-102731 (GCVE-0-2026-102731)

Vulnerability from cvelistv5 – Published: 2026-10-02 09:22 – Updated: 2026-10-02 09:22

Title

Apache Directory LDAP API: Denial of service via excessive memory allocation in BER decode

Summary

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.

Severity

No CVSS data available.

CWE

CWE-789 - Memory allocation with excessive size value

Assigner

apache mitre root Scorecard

References

1 reference

URL	Tags
https://lists.apache.org/thread.html/b8kg8881pc0v…	vendor-advisory

Impacted products

1 product

Vendor	Product	Version
Apache Software Foundation	Apache Directory LDAP API	Affected: 1.2.0 , < 1.2.9 (semver)

Credits

Claude Security The Apache Software Foundation

Show details on NVD website

JSON

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          "packageURL": "pkg:maven/org.apache.directory.api/api-asn1-ber",
          "product": "Apache Directory LDAP API",
          "vendor": "Apache Software Foundation",
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              "lessThan": "1.2.9",
              "status": "affected",
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              "versionType": "semver"
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          "type": "finder",
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    "datePublished": "2026-10-02T09:22:00.813Z",
    "dateReserved": "2026-09-29T16:17:56.332Z",
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Sightings

Author	Source	Type	Date	Other

Nomenclature

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Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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GHSA-H24G-PJPF-8F2M

CVE-2026-102731 (GCVE-0-2026-102731)

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