High 7.5

Vulnerability in 389 Directory Server

CVE-2026-18453 First seen on SecPulse Sep 8, 00:17

AI summary

Produced by SecPulse using an external AI model; it may contain mistakes. Check the original description and references below before acting on it.

A vulnerability tracked as CVE-2026-18453 has been found in 389 Directory Server.
Risk of unauthorized operations or information disclosure. CVSS score: 7.5/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "389 Directory Server CVE-2026-18453" on the vendor's site.

CVE-2026-18453 (389 Directory Server) — CWE-476 / CVSS v3 7.5
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.

What is the problem

A vulnerability (CWE-476) exists in 389 Directory Server.

Affected scope

Check the vendor advisory for the affected versions of 389 Directory Server.

Severity

Severity: High (CVSS 7.5/10). Risk of unauthorized operations or information disclosure.

How to fix

Update to the patched release per vendor advisory.

Workaround

Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.

Detection

Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.

Response actions

Concrete steps and command examples for SOC/SRE teams to execute in order

1
Identify exposureidentify
```
Audit SBOM/dependencies for affected components.
```
資産台帳・SBOM・依存マニフェストで 389 Directory Server を使っているサービスとバージョンを洗い出す。
2
Post-deployment verificationverify
```
Confirm patched version is live in production
```
パッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。

Fix status by distribution

Records published by each distribution for this CVE. Fixed versions differ by release; check each link.

Debian DEBIAN-CVE-2026-18453 389-ds-base No fixed version in this record
Ubuntu UBUNTU-CVE-2026-18453 389-ds-base No fixed version in this record

Original description The description as published by the source.

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.

Source: NIST National Vulnerability Database NVD GitHub Advisory

AI summary

Response actions

Fix status by distribution

References