# CVE-2026-11788: 389-ds-base: 389-ds-base: null pointer dereference in deref control plugin ber parser

> An unauthenticated remote attacker can crash the LDAP server by triggering a null pointer dereference in the dereference control plugin during memory pressure.

- **Severity:** Medium 5.9 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 9 Jun 2026
- **Updated:** 8 Oct 2026
- **Also known as:** DEBIAN-CVE-2026-11788, GHSA-x2wj-4r98-4867, UBUNTU-CVE-2026-11788

## What is CVE-2026-11788?

CVE-2026-11788 is a medium-severity vulnerability in Redhat Enterprise Linux, published on 9 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A flaw was found in 389 Directory Server. The dereference control plugin does not check for allocation failure before using a BER structure, allowing an unauthenticated remote attacker to crash the LDAP server when the system is under memory pressure.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2026-11788?

It affects 3 products.


Products: Redhat 389 Directory Server, Redhat Directory Server, Redhat Enterprise Linux.

## How do I fix CVE-2026-11788?

Apply the vendor's patch.

## Is CVE-2026-11788 being exploited?

There is no known exploitation of CVE-2026-11788 in the wild and no public exploit code.

## Other vulnerabilities in Redhat Enterprise Linux

- [CVE-2026-11770](https://insights.sbomify.com/CVE-2026-11770/): 389-ds-base: 389-ds-base: pre-auth ldap filter injection in cleanallruv status check (high 7.5)
- [CVE-2026-15722](https://insights.sbomify.com/CVE-2026-15722/): Memory corruption in Red Hat Directory Server 11.5 E4S for RHEL 8 (high 7.5)
- [CVE-2026-9064](https://insights.sbomify.com/CVE-2026-9064/): Denial of service in Red Hat Directory Server 11.5 E4S for RHEL 8 (high 7.5)
- [CVE-2010-2222](https://insights.sbomify.com/CVE-2010-2222/): Null dereference in Red Hat Directory Server (high 7.5)
- [CVE-2026-11611](https://insights.sbomify.com/CVE-2026-11611/): 389-ds-base: 389-ds-base: content sync plugin unbounded queue growth and race conditions (medium 6.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-11788 and fix it if it is affected.

What it is: CVE-2026-11788 is a medium-severity vulnerability in Redhat Enterprise Linux, published on 9 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-11788 in the wild and no public exploit code.

Affected product: Redhat Enterprise Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-11788/ (Markdown: https://insights.sbomify.com/CVE-2026-11788/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-11788
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-11788
- OSV: https://osv.dev/vulnerability/CVE-2026-11788

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-11788/
Summaries are generated and may contain mistakes; the official description above is the record.