# CVE-2026-18453

## Summary

- **CVE ID:** CVE-2026-18453
- **Severity:** HIGH
- **CVSS Score:** 7.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
- **CWE:** CWE-476
- **Published:** Sep 7, 2026
- **Last Modified:** Sep 9, 2026

## Description

A flaw was found in 389 Directory Server. A missing NULL pointer check in the paged results handling of op_shared_search allows an unauthenticated remote attacker to crash the LDAP server by sending a crafted sequence of search requests using the USE_ONE_BACKEND control, resulting in denial of service.

## Affected Products

- Red Hat — Red Hat Enterprise Linux 7 Extended Lifecycle Support (0:1.3.11.1-15.el7_9)
- Red Hat — Red Hat Directory Server 11.7 E4S for RHEL 8 (8080020260903102346.f969626e)
- Red Hat — Red Hat Directory Server 12.2 E4S for RHEL 9 (9020020260903155914.1674d574)
- Red Hat — Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support (8040020260901171549.96015a92)
- Red Hat — Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On (8040020260901171549.96015a92)
- Red Hat — Red Hat Enterprise Linux 8.8 Telecommunications Update Service (8080020260831180218.6dbb3803)
- Red Hat — Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions (8080020260831180218.6dbb3803)
- Red Hat — Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions (0:2.2.4-22.el9_2)
- Red Hat — Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions (0:2.4.5-29.el9_4)
- Red Hat — Red Hat Enterprise Linux 10.0 Extended Update Support (0:3.0.6-21.el10_0)
- Red Hat — Red Hat Enterprise Linux 9.6 Extended Update Support (0:2.6.1-24.el9_6)
- Red Hat — Red Hat Enterprise Linux 8 (8100020260904155442.25e700aa)
- Red Hat — Red Hat Enterprise Linux 9 (0:2.8.0-10.el9_8)
- Red Hat — Red Hat Directory Server 11.9 for RHEL 8 (8100020260904171440.37ed7c03)
- Red Hat — Red Hat Directory Server 12.4 E4S for RHEL 9 (9040020260903102623.1674d574)
- Red Hat — Red Hat Enterprise Linux 10 (0:3.2.0-10.el10_2)
- Red Hat — Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support (8060020260901145727.824efc52)
- Red Hat — Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On (8060020260901145727.824efc52)
- Red Hat — Red Hat Directory Server 13.2 (1788851765)

## References

- [CNA](https://access.redhat.com/security/cve/CVE-2026-18453)
- [CNA](https://bugzilla.redhat.com/show_bug.cgi?id=2509696)
- [CNA](https://access.redhat.com/errata/RHSA-2026:64771)
- [CNA](https://access.redhat.com/errata/RHSA-2026:64776)
- [CNA](https://access.redhat.com/errata/RHSA-2026:64778)
- [CNA](https://access.redhat.com/errata/RHSA-2026:64779)
- [CNA](https://access.redhat.com/errata/RHSA-2026:64781)
- [CNA](https://access.redhat.com/errata/RHSA-2026:64789)
- [CNA](https://access.redhat.com/errata/RHSA-2026:64792)
- [CNA](https://access.redhat.com/errata/RHSA-2026:64783)
- [CNA](https://access.redhat.com/errata/RHSA-2026:64804)
- [CNA](https://access.redhat.com/errata/RHSA-2026:64791)
- [CNA](https://access.redhat.com/errata/RHSA-2026:64784)
- [CNA](https://access.redhat.com/errata/RHSA-2026:64780)
- [CNA](https://access.redhat.com/errata/RHSA-2026:64785)
- [CNA](https://access.redhat.com/errata/RHSA-2026:64790)
- [CNA](https://access.redhat.com/errata/RHSA-2026:64793)
- [CNA](https://access.redhat.com/errata/RHSA-2026:65119)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.85%
- **EPSS Percentile:** 55.9

---
_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-10._