# CVE-2018-17031: Gogs XSS Vulnerability

> An attacker can trigger XSS in Gogs by uploading a crafted .eml file due to missing MIME type sniffing headers.

- **Severity:** Medium 6.1 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/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:** Yes
- **Published:** 14 Sep 2018
- **Updated:** 5 Aug 2024
- **Also known as:** GHSA-px5r-fqj6-r2f8, GO-2023-1972

## What is CVE-2018-17031?

CVE-2018-17031 is a medium-severity cross-site scripting vulnerability in n/a, published on 14 Sep 2018. 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

In Gogs 0.11.53, an attacker can use a crafted .eml file to trigger MIME type sniffing, which leads to XSS, as demonstrated by Internet Explorer, because an "X-Content-Type-Options: nosniff" header is not sent.

Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation)

## Which versions are affected by CVE-2018-17031?

3 open source packages ship an affected version, including gogs.io/gogs. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `gogs.io/gogs` | Go | All versions | 0.12.0 |
| `gogs.io/gogs` | Go | All versions | 0.12.0 |
| `gogs.io/gogs` | Go | All versions | 0.12.0 |

Products: Gogs Gogs.

## How do I fix CVE-2018-17031?

Upgrade gogs.io/gogs to 0.12.0 or later.

## Is CVE-2018-17031 being exploited?

There is no known exploitation of CVE-2018-17031 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2025-8110](https://insights.sbomify.com/CVE-2025-8110/): Gogs Path Traversal (high 8.7, exploited in the wild)
- [CVE-2024-56731](https://insights.sbomify.com/CVE-2024-56731/): Gogs deletion of internal files allows remote command execution (critical 10.0)
- [CVE-2022-1884](https://insights.sbomify.com/CVE-2022-1884/): Remote Command Execution in gogs/gogs (critical 10.0)
- [CVE-2022-1986](https://insights.sbomify.com/CVE-2022-1986/): OS Command Injection in gogs/gogs (critical 10.0)
- [CVE-2022-1992](https://insights.sbomify.com/CVE-2022-1992/): Path Traversal in gogs/gogs (critical 10.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-17031 and fix it if it is affected.

What it is: CVE-2018-17031 is a medium-severity cross-site scripting vulnerability in n/a, published on 14 Sep 2018. 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-2018-17031 in the wild and no public exploit code.

Affected packages and fixed versions:
- gogs.io/gogs (Go): affected all versions; fixed in 0.12.0
- gogs.io/gogs (Go): affected all versions; fixed in 0.12.0
- gogs.io/gogs (Go): affected all versions; fixed in 0.12.0

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-2018-17031/ (Markdown: https://insights.sbomify.com/CVE-2018-17031/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-17031
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-17031
- OSV: https://osv.dev/vulnerability/CVE-2018-17031

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-17031/
Summaries are generated and may contain mistakes; the official description above is the record.