# CVE-2021-43185: Other in n/a

> Attackers can inject malicious Host headers in JetBrains YouTrack, potentially bypassing security controls or poisoning caches.

- **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:** 9 Nov 2021
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-vv73-h85j-cqvw

## What is CVE-2021-43185?

CVE-2021-43185 is a critical vulnerability in Jetbrains Youtrack, published on 9 Nov 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

JetBrains YouTrack before 2021.3.23639 is vulnerable to Host header injection.

Weakness: CWE-74 (Improper Neutralization of Special Elements in Output Used by a Downstream Component)

## Which versions are affected by CVE-2021-43185?

It affects 1 product.


Products: Jetbrains Youtrack.

## How do I fix CVE-2021-43185?

No fix has been published for CVE-2021-43185 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-43185 being exploited?

There is no known exploitation of CVE-2021-43185 in the wild and no public exploit code.

## Other vulnerabilities in Jetbrains Youtrack

- [CVE-2026-62422](https://insights.sbomify.com/CVE-2026-62422/): Auth bypass in YouTrack (critical 10.0)
- [CVE-2022-24442](https://insights.sbomify.com/CVE-2022-24442/): Code injection in n/a (critical 9.8)
- [CVE-2021-25770](https://insights.sbomify.com/CVE-2021-25770/): Code injection in n/a (critical 9.8)
- [CVE-2019-12850](https://insights.sbomify.com/CVE-2019-12850/): SQL injection in n/a (critical 9.8)
- [CVE-2019-12852](https://insights.sbomify.com/CVE-2019-12852/): Server-side request forgery in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-43185 and fix it if it is affected.

What it is: CVE-2021-43185 is a critical vulnerability in Jetbrains Youtrack, published on 9 Nov 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-2021-43185 in the wild and no public exploit code.

Affected product: Jetbrains Youtrack. 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-2021-43185/ (Markdown: https://insights.sbomify.com/CVE-2021-43185/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-43185
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-43185
- OSV: https://osv.dev/vulnerability/CVE-2021-43185

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-43185/
Summaries are generated and may contain mistakes; the official description above is the record.