# CVE-2026-104286: Fortinet FortiMail Path Traversal

> Unauthenticated attackers can write arbitrary files on FortiMail systems via crafted HTTP requests, potentially leading to code execution.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C`)
- **Exploited in the wild:** Yes, since 1 Oct 2026 (CISA KEV)
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 1 Oct 2026
- **Updated:** 28 Oct 2026
- **Also known as:** GHSA-6gxc-3vv7-7w24

## What is CVE-2026-104286?

CVE-2026-104286 is a critical path traversal vulnerability in Fortinet FortiMail, published on 1 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

An improper limitation of a pathname to a restricted directory ('path traversal') vulnerability in Fortinet FortiMail 8.0.0 through 8.0.1, FortiMail 7.6.0 through 7.6.6, FortiMail 7.4.0 through 7.4.8, FortiMail 7.2.0 through 7.2.9, FortiMail 7.0 all versions may allow an unauthenticated attacker to write arbitrary files on the underlying system via crafted HTTP or HTTPS requests.

Weakness: CWE-22 (Improper Limitation of a Pathname to a Restricted Directory)

## Which versions are affected by CVE-2026-104286?

It affects 1 product.


Products: Fortinet Fortimail.

## How do I fix CVE-2026-104286?

No fix has been published for CVE-2026-104286 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 4 Oct 2026.

## Is CVE-2026-104286 being exploited?

Yes. Attackers have exploited CVE-2026-104286 in the wild since at least 1 Oct 2026.

Public exploit code:

- https://github.com/ShadowForge-Cyber/CVE-2026-104286-POC (github_poc): https://github.com/ShadowForge-Cyber/CVE-2026-104286-POC
- A complete guide and workflow for integrating Agile sprints with DevOps CI/CD pipelines. (github_poc): https://github.com/techupdate24/fortimail-zero-day-cve-2026-104286
- FortiMail CVE-2026-104286 (CVSS 9.8) 점검·대응 도구 (버전 확인, IoC 점검, 완화·패치 체크리스트) (github_poc): https://github.com/kh20134/fortimail-cve-2026-104286-response
- Offline FortiMail evidence checker for CVE-2026-104286. FortiMail version and deployment evidence. Standalone Python; JSON/CSV/HTML reports; no exploit payloads. (github_poc): https://github.com/CompleteTech-Security/fortimail-cve-2026-104286-check
- Exploit for CVE-2026-104286 — FortiMail: Unauthenticated Arbitrary File Write → Code Execution (github_poc): https://github.com/maxprog-svg/CVE-2026-104286

## Other vulnerabilities in Fortinet FortiMail

- [CVE-2021-36166](https://insights.sbomify.com/CVE-2021-36166/): Auth bypass in Fortinet FortiMail (critical 9.8)
- [CVE-2021-24007](https://insights.sbomify.com/CVE-2021-24007/): SQL injection in Fortinet FortiMail (critical 9.8)
- [CVE-2020-9294](https://insights.sbomify.com/CVE-2020-9294/): Auth bypass in FortiMail (critical 9.8)
- [CVE-2023-47539](https://insights.sbomify.com/CVE-2023-47539/): Auth bypass in FortiMail (critical 9.0)
- [CVE-2021-24013](https://insights.sbomify.com/CVE-2021-24013/): Path traversal in Fortinet FortiMail (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-104286 and fix it if it is affected.

What it is: CVE-2026-104286 is a critical path traversal vulnerability in Fortinet FortiMail, published on 1 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: Yes. Attackers have exploited CVE-2026-104286 in the wild since at least 1 Oct 2026.

Affected product: Fortinet FortiMail. 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-2026-104286/ (Markdown: https://insights.sbomify.com/CVE-2026-104286/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-104286
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-104286
- OSV: https://osv.dev/vulnerability/CVE-2026-104286

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-104286/
Summaries are generated and may contain mistakes; the official description above is the record.