# CVE-2021-36777: login-proxy sends password to attacker-provided domain

> Attackers can trick users into sending clear-text credentials to a malicious server via a manipulated login form in the openSUSE Build Service login proxy.

- **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 9 Mar 2022
- **Updated:** 16 Sep 2024
- **Also known as:** GHSA-3pc4-pj89-2j67

## What is CVE-2021-36777?

CVE-2021-36777 is a high-severity vulnerability in openSUSE Build service, published on 9 Mar 2022. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

A Reliance on Untrusted Inputs in a Security Decision vulnerability in the login proxy of the openSUSE Build service allowed attackers to present users with a expected login form that then sends the clear text credentials to an attacker specified server. This issue affects: openSUSE Build service login-proxy-scripts versions prior to dc000cdfe9b9b715fb92195b1a57559362f689ef.

Weakness: CWE-807 (Reliance on Untrusted Inputs in a Security Decision)

## Which versions are affected by CVE-2021-36777?

It affects 1 product.


Products: Opensuse Open Build Service.

## How do I fix CVE-2021-36777?

No fix has been published for CVE-2021-36777 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-36777 being exploited?

There is no known exploitation of CVE-2021-36777 in the wild and no public exploit code.

## Other vulnerabilities in openSUSE Build service

- [CVE-2022-21949](https://insights.sbomify.com/CVE-2022-21949/): Multiple XXE vulnerabilities in OBS (high 8.8)
- [CVE-2013-3703](https://insights.sbomify.com/CVE-2013-3703/): No write permission check in change_role command (high 8.8)
- [CVE-2014-0594](https://insights.sbomify.com/CVE-2014-0594/): CSRF protection incorrectly disabled (high 8.8)
- [CVE-2011-3178](https://insights.sbomify.com/CVE-2011-3178/): openbuildservice webui code injection (high 8.1)
- [CVE-2014-0593](https://insights.sbomify.com/CVE-2014-0593/): sed command injection (high 7.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-36777 and fix it if it is affected.

What it is: CVE-2021-36777 is a high-severity vulnerability in openSUSE Build service, published on 9 Mar 2022. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2021-36777 in the wild and no public exploit code.

Affected product: openSUSE Build service. 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-2021-36777/ (Markdown: https://insights.sbomify.com/CVE-2021-36777/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-36777
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-36777
- OSV: https://osv.dev/vulnerability/CVE-2021-36777

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-36777/
Summaries are generated and may contain mistakes; the official description above is the record.