Is itCheck something

No. CVE-2026-76519

Cisco email security gateways let attackers write files

Being used now

Yes. Attackers are using this right now.

Organizations that filter email with a Cisco Secure Email Gateway.

What to do

Apply Cisco's security update for Secure Email Gateway.

Confirmed in attacksOct 14, 2026
ProductCisco Secure Email Gateway
GitHub repos1
Attack likelihood, next 30 days2.2%

Attack likelihood is EPSS, a daily estimate from FIRST.org of how likely this bug is to be used in attacks in the next 30 days.

The official description

Cisco Secure Email Gateway contains a relative path traversal vulnerability that could allow an unauthenticated, remote attacker to write arbitrary files on the underlying operating system.

For your tech helper or AI assistant

A read-only checklist. Paste it into Claude, ChatGPT or a coding agent; it only looks and changes nothing.

Read-only check, change nothing, send nothing anywhere.
Is Cisco Secure Email Gateway (CVE-2026-76519) installed or running on this machine or in this project?
1. Find every copy and its version (apps, packages, containers, lockfiles).
2. Compare each version against the vendor's fixed version for CVE-2026-76519. Quote the vendor page you used.
3. Report a table: where, version, fixed version, status (exposed / fixed / not installed / unsure).
4. List the exact update steps, but do not run them.
Download playbook (.md)

Code on GitHub

Repos named after this bug. Some are scanners or write-ups, some are working attack code. Do not run them on a machine you care about.

Sources