CVE-2026-11884Network attack vector

Server crash via undersized objectclass serialization buffer

Published Jun 10, 2026 · Updated Jun 10, 2026

Heap buffer overflow in Red Hat Directory Server allows remote authenticated users to crash the server via crafted objectclass SUP values. The read_schema_dse() and schema_oc_to_string() paths omit the oc_superior length from allocation calculations before strcat() appends the value. Reachability requires Directory Manager privileges or control of a replication supplier, and the demonstrated consequence is a service crash.

CVSS severity6.5
Medium
EPSS probability0.35%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Heap buffer overflow in Red Hat Directory Server allows remote authenticated users to crash the server via crafted objectclass SUP values. The read_schema_dse() and schema_oc_to_string() paths omit the oc_superior length from allocation calculations before strcat() appends the value. Reachability requires Directory Manager privileges or control of a replication supplier, and the demonstrated consequence is a service crash.

The record

CVE
CVE-2026-11884
Published
Jun 10, 2026
Updated
Jun 10, 2026
Vendor
389 Directory Server
Product
Red Hat Directory Server
Classifications
CWE-122, T1499
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Jun 10, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 10, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

389 Directory Server · Red Hat Directory ServerAffected versions are unavailable in this record.
389 Directory Server · Red Hat Enterprise Linux 10Affected versions are unavailable in this record.
389 Directory Server · Red Hat Enterprise Linux 7Affected versions are unavailable in this record.
389 Directory Server · Red Hat Enterprise Linux 9Affected versions are unavailable in this record.
389 Directory Server · Red Hat Enterprise Linux 8Affected versions are unavailable in this record.

Published CVSS scores

6.5Red HatCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-122Heap-based Buffer Overflow
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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