# CVE-2026-103547: Auth bypass in OpenBSD

> Remote attackers can impersonate users via ldapd authentication result reuse, requiring ldapd to be enabled.

- **Severity:** Critical 9.2 (`CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 30 Sep 2026
- **Updated:** 30 Sep 2026
- **Also known as:** GHSA-f239-ggxr-g679

## What is CVE-2026-103547?

CVE-2026-103547 is a critical authentication bypass vulnerability in OpenBSD, published on 30 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

In ldapd in OpenBSD 7.8 before errata 057 and 7.9 before errata 021, delegated BSD authentication results are correlated only by the LDAP child process client file descriptor and LDAP message ID. After a connection closes, a later connection that reuses the same file descriptor and message ID can receive the earlier authentication result. A remote attacker who can reach ldapd can complete a Bind as another identity. A missing connection can also cause a NULL pointer dereference. (ldapd is not enabled by default.)

Weakness: CWE-863 (Incorrect Authorization)

## Which versions are affected by CVE-2026-103547?


## How do I fix CVE-2026-103547?

No fix has been published for CVE-2026-103547 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-103547 being exploited?

There is no known exploitation of CVE-2026-103547 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-103547 and fix it if it is affected.

What it is: CVE-2026-103547 is a critical authentication bypass vulnerability in OpenBSD, published on 30 Sep 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-2026-103547 in the wild and no public exploit code.

Affected product: OpenBSD. 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-2026-103547/ (Markdown: https://insights.sbomify.com/CVE-2026-103547/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-103547
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-103547
- OSV: https://osv.dev/vulnerability/CVE-2026-103547

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-103547/
Summaries are generated and may contain mistakes; the official description above is the record.