# CVE-2026-76519: Cisco Secure Email Gateway Relative Path Traversal

> Unauthenticated remote attackers can write arbitrary files and execute commands with root privileges via crafted email attachments when the file reputation service is enabled.

- **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:** Yes, since 14 Oct 2026 (CISA KEV)
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 14 Oct 2026
- **Updated:** 15 Oct 2026
- **Also known as:** GHSA-6rc3-jwq8-jm3v

## What is CVE-2026-76519?

CVE-2026-76519 is a critical path traversal vulnerability in Cisco Asyncos, published on 14 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability in the Advanced Malware Protection (AMP) feature of Cisco Secure Email Gateway could allow an unauthenticated, remote attacker to write arbitrary files on the underlying operating system.

This vulnerability is due to improper handling of email attachments when the file reputation service is enabled. An attacker could exploit this vulnerability by sending an email that contains a crafted attachment through an affected device. A successful exploit could allow the attacker to write arbitrary files and execute commands with root privileges on the underlying operating system.

Weakness: CWE-23 (Relative Path Traversal)

## Which versions are affected by CVE-2026-76519?

It affects 1 product.


Products: Cisco Asyncos.

## How do I fix CVE-2026-76519?

No fix has been published for CVE-2026-76519 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 17 Oct 2026.

## Is CVE-2026-76519 being exploited?

Yes. Attackers have exploited CVE-2026-76519 in the wild since at least 14 Oct 2026.

Public exploit code:

- Unauthenticated remote code execution on Cisco Secure Email Gateway via crafted email attachment. Path traversal in AMP File Reputation handling allows arbitrary file write as root when the service is enabled on a mail policy. (github_poc): https://github.com/Mickysalivan/CVE-2026-76519-Proof-of-concept

## Other vulnerabilities in Cisco Asyncos

- [CVE-2025-20393](https://insights.sbomify.com/CVE-2025-20393/): Cisco Multiple Products Improper Input Validation (critical 10.0, exploited in the wild)
- [CVE-2026-76461](https://insights.sbomify.com/CVE-2026-76461/): Cisco Secure Email Gateway SQL Injection (critical 9.8, exploited in the wild)
- [CVE-2024-20435](https://insights.sbomify.com/CVE-2024-20435/): Command injection in Cisco Secure Web Appliance (high 8.8)
- [CVE-2019-15956](https://insights.sbomify.com/CVE-2019-15956/): Cisco Web Security Appliance Unauthorized Device Reset Vulnerability (high 8.8)
- [CVE-2021-34698](https://insights.sbomify.com/CVE-2021-34698/): Cisco Web Security Appliance Proxy Service Denial of Service Vulnerability (high 8.6)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-76519 and fix it if it is affected.

What it is: CVE-2026-76519 is a critical path traversal vulnerability in Cisco Asyncos, published on 14 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-2026-76519 in the wild since at least 14 Oct 2026.

Affected product: Cisco Asyncos. 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-2026-76519/ (Markdown: https://insights.sbomify.com/CVE-2026-76519/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-76519
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-76519
- OSV: https://osv.dev/vulnerability/CVE-2026-76519

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-76519/
Summaries are generated and may contain mistakes; the official description above is the record.