# CVE-2021-32744: Unauthenticated attacker could gain access to currently open files

> Unauthenticated attackers can access files opened by other users by guessing file identifiers, exposing sensitive data in Collabora Online.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 21 Jul 2021
- **Updated:** 3 Aug 2024

## What is CVE-2021-32744?

CVE-2021-32744 is a critical missing authorization vulnerability in CollaboraOnline online, published on 21 Jul 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Collabora Online is a collaborative online office suite. In versions prior to 4.2.17-1 and version 6.4.9-5, unauthenticated attackers are able to gain access to files which are currently opened by other users in the Collabora Online editor. For successful exploitation the attacker is required to guess the file identifier - the predictability of this file identifier is dependent on external file-storage implementations (this is a potential "IDOR" - Insecure Direct Object Reference - vulnerability). Versions 4.2.17-1 and 6.4.9-5 contain patches for this issue. There is no known workaround except updating the Collabora Online application to one of the patched releases.

Weakness: CWE-639 (Authorization Bypass Through User-Controlled Key)

## Which versions are affected by CVE-2021-32744?

It affects 1 product.


Products: Collabora Online.

## How do I fix CVE-2021-32744?

No fix has been published for CVE-2021-32744 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-32744 being exploited?

There is no known exploitation of CVE-2021-32744 in the wild and no public exploit code.

## Other vulnerabilities in CollaboraOnline online

- [CVE-2026-110447](https://insights.sbomify.com/CVE-2026-110447/): Collabora Online – Built-in CODE Server OS Command Injection (critical 9.2, exploited in the wild)
- [CVE-2021-43817](https://insights.sbomify.com/CVE-2021-43817/): Reflected Cross-Site-Scripting vulnerability in Collabora Online (high 8.2)
- [CVE-2021-32745](https://insights.sbomify.com/CVE-2021-32745/): Reflected Cross-Site-Scripting vulnerability (high 7.3)
- [CVE-2025-66208](https://insights.sbomify.com/CVE-2025-66208/): Configuration-Dependent RCE (OS Command Injection) in richdocumentscode proxy (high 7.2)
- [CVE-2024-45045](https://insights.sbomify.com/CVE-2024-45045/): JavaScript Injection via url encoded values in links in Collabora Office Android (medium 6.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-32744 and fix it if it is affected.

What it is: CVE-2021-32744 is a critical missing authorization vulnerability in CollaboraOnline online, published on 21 Jul 2021. 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-2021-32744 in the wild and no public exploit code.

Affected product: CollaboraOnline online. 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-2021-32744/ (Markdown: https://insights.sbomify.com/CVE-2021-32744/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-32744
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-32744
- OSV: https://osv.dev/vulnerability/CVE-2021-32744

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-32744/
Summaries are generated and may contain mistakes; the official description above is the record.