# CVE-2026-41243: OpenLearn's pending forum posts remain publicly readable by direct ID when moderation mode is enabled

> Attackers can read unapproved forum posts via direct UUID access when moderation mode is enabled, bypassing visibility restrictions.

- **Severity:** Medium 6.9 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/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:** 23 Apr 2026
- **Updated:** 23 Apr 2026
- **Also known as:** GHSA-4rv3-hfh6-vqvm

## What is CVE-2026-41243?

CVE-2026-41243 is a medium-severity missing authorization vulnerability in siemvk OpenLearn, published on 23 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

OpenLearn is open-source educational forum software. Prior to commit 844b2a40a69d0c4911580fe501923f0b391313ab, when `safeMode` is enabled, unapproved forum posts are hidden from the public list, but the direct post-read procedure still returns the full post to anyone with the post UUID. Commit 844b2a40a69d0c4911580fe501923f0b391313ab fixes the issue.

Weakness: CWE-284 (Improper Access Control)

## Which versions are affected by CVE-2026-41243?

It affects 1 product.


Products: Siemvk Openlearn.

## How do I fix CVE-2026-41243?

No fix has been published for CVE-2026-41243 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-41243 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-41243 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-41243 and fix it if it is affected.

What it is: CVE-2026-41243 is a medium-severity missing authorization vulnerability in siemvk OpenLearn, published on 23 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-41243 exists.

Affected product: siemvk OpenLearn. 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-2026-41243/ (Markdown: https://insights.sbomify.com/CVE-2026-41243/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-41243
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-41243
- OSV: https://osv.dev/vulnerability/CVE-2026-41243

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-41243/
Summaries are generated and may contain mistakes; the official description above is the record.