# CVE-2026-11774: 389-ds-base: 389-ds-base: integer overflow in sasl packet length bypasses size limit leading to heap buffer overflow

> Remote attackers with valid SASL credentials can trigger an integer overflow to bypass size limits, causing heap buffer overflow and potential remote code execution.

- **Severity:** High 7.6 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 11 Jun 2026
- **Updated:** 15 Jul 2026
- **Also known as:** CLSA-2026-1784639752, DEBIAN-CVE-2026-11774, GHSA-6mrg-rm5v-2c3q, UBUNTU-CVE-2026-11774

## What is CVE-2026-11774?

CVE-2026-11774 is a high-severity vulnerability in Red Hat Directory Server 11.5 E4S for RHEL 8, published on 11 Jun 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

An integer overflow flaw was found in the SASL I/O layer of 389 Directory Server (389-ds-base). In sasl_io_start_packet(), adding sizeof(uint32_t) to a crafted SASL packet length prefix of 0xFFFFFFFC causes unsigned wraparound to zero, bypassing the nsslapd-maxsasliosize limit and leading to a heap buffer overflow of up to approximately 2 megabytes of attacker-controlled data. After a successful SASL bind with integrity protection (SSF > 0), a remote attacker can cause a Denial of Service (DoS) or achieve Remote Code Execution (RCE). In FreeIPA and Red Hat Identity Management deployments, any domain user with a valid Kerberos ticket, enrolled host, or service account can trigger this vulnerability over the network. This flaw is independent of CVE-2025-14905, which patched schema.c only and did not modify sasl_io.c.

Weakness: CWE-190 (Integer Overflow or Wraparound)

## Which versions are affected by CVE-2026-11774?


## How do I fix CVE-2026-11774?

Apply the vendor's patch.

## Is CVE-2026-11774 being exploited?

There is no known exploitation of CVE-2026-11774 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-11774 and fix it if it is affected.

What it is: CVE-2026-11774 is a high-severity vulnerability in Red Hat Directory Server 11.5 E4S for RHEL 8, published on 11 Jun 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-11774 in the wild and no public exploit code.

Affected product: Red Hat Directory Server 11.5 E4S for RHEL 8. 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-2026-11774/ (Markdown: https://insights.sbomify.com/CVE-2026-11774/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-11774
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-11774
- OSV: https://osv.dev/vulnerability/CVE-2026-11774

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-11774/
Summaries are generated and may contain mistakes; the official description above is the record.