# CVE-2026-11884: Memory corruption in Red Hat Directory Server 11

> An attacker with Directory Manager privileges can cause a server crash via heap buffer overflow in schema serialization.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 10 Jun 2026
- **Updated:** 30 Jun 2026
- **Also known as:** DEBIAN-CVE-2026-11884, GHSA-f4g5-r76v-qg3p, UBUNTU-CVE-2026-11884

## What is CVE-2026-11884?

CVE-2026-11884 is a medium-severity memory corruption vulnerability in Red Hat Directory Server 11, published on 10 Jun 2026. An attacker needs administrator access to exploit it, with no action from the victim.

### Official description

A heap buffer overflow flaw was found in 389 Directory Server. When serializing objectclass definitions, the oc_superior (SUP) field length is omitted from buffer size calculations in read_schema_dse() and schema_oc_to_string(), but the field is still written via strcat(). An attacker with Directory Manager privileges, or a compromised replication supplier, can trigger a server crash by creating objectclasses with long SUP values. This is an incomplete fix variant of CVE-2025-14905.

Weakness: CWE-122 (Heap-based Buffer Overflow)

## Which versions are affected by CVE-2026-11884?


## How do I fix CVE-2026-11884?

Apply the vendor's patch.

## Is CVE-2026-11884 being exploited?

There is no known exploitation of CVE-2026-11884 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-11884 and fix it if it is affected.

What it is: CVE-2026-11884 is a medium-severity memory corruption vulnerability in Red Hat Directory Server 11, published on 10 Jun 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-11884 in the wild and no public exploit code.

Affected product: Red Hat Directory Server 11. 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-2026-11884/ (Markdown: https://insights.sbomify.com/CVE-2026-11884/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-11884
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-11884
- OSV: https://osv.dev/vulnerability/CVE-2026-11884

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-11884/
Summaries are generated and may contain mistakes; the official description above is the record.