# CVE-2026-21789: HCL Connections is vulnerable to broken access control

> An unauthorized user can update data in HCL Connections due to broken access control, requiring administrators to apply vendor patches.

- **Severity:** Medium 4.6 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 18 May 2026
- **Updated:** 18 May 2026
- **Also known as:** GHSA-hx5c-g9jj-chxv

## What is CVE-2026-21789?

CVE-2026-21789 is a medium-severity missing authorization vulnerability in HCLSoftware Connections, published on 18 May 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

HCL Connections contains a broken access control vulnerability that may allow unauthorized user to update data in certain scenarios.

Weakness: CWE-863 (Incorrect Authorization)

## Which versions are affected by CVE-2026-21789?


## How do I fix CVE-2026-21789?

No fix has been published for CVE-2026-21789 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-21789 being exploited?

There is no known exploitation of CVE-2026-21789 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-21789 and fix it if it is affected.

What it is: CVE-2026-21789 is a medium-severity missing authorization vulnerability in HCLSoftware Connections, published on 18 May 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-21789 in the wild and no public exploit code.

Affected product: HCLSoftware Connections. 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-2026-21789/ (Markdown: https://insights.sbomify.com/CVE-2026-21789/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-21789
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-21789
- OSV: https://osv.dev/vulnerability/CVE-2026-21789

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-21789/
Summaries are generated and may contain mistakes; the official description above is the record.