# CVE-2021-40889: Code injection in n/a

> Attackers can inject malicious PHP code into password files via the password change function, leading to remote code execution on the server.

- **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:** 11 Oct 2021
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-hcrw-87mg-3f84

## What is CVE-2021-40889?

CVE-2021-40889 is a critical code injection vulnerability in n/a, published on 11 Oct 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

CMSUno version 1.7.2 is affected by a PHP code execution vulnerability. sauvePass action in {webroot}/uno/central.php file calls to file_put_contents() function to write username in password.php file when a user successfully changed their password. The attacker can inject malicious PHP code into password.php and then use the login function to execute code.

Weakness: CWE-94 (Improper Control of Generation of Code)

## Which versions are affected by CVE-2021-40889?

It affects 1 product.


Products: Cmsuno Project Cmsuno.

## How do I fix CVE-2021-40889?

No fix has been published for CVE-2021-40889 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-40889 being exploited?

There is no known exploitation of CVE-2021-40889 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2020-25538](https://insights.sbomify.com/CVE-2020-25538/): Code injection in n/a (high 8.8)
- [CVE-2020-25557](https://insights.sbomify.com/CVE-2020-25557/): Code injection in n/a (high 8.8)
- [CVE-2020-15600](https://insights.sbomify.com/CVE-2020-15600/): Cross-site request forgery in n/a (medium 6.5)
- [CVE-2018-15567](https://insights.sbomify.com/CVE-2018-15567/): Cross-site scripting in n/a (medium 6.1)
- [CVE-2021-36654](https://insights.sbomify.com/CVE-2021-36654/): Cross-site scripting in n/a (medium 5.4)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-40889 and fix it if it is affected.

What it is: CVE-2021-40889 is a critical code injection vulnerability in n/a, published on 11 Oct 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-2021-40889 in the wild and no public exploit code.

Affected product: n/a. 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-2021-40889/ (Markdown: https://insights.sbomify.com/CVE-2021-40889/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-40889
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-40889
- OSV: https://osv.dev/vulnerability/CVE-2021-40889

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-40889/
Summaries are generated and may contain mistakes; the official description above is the record.