# Cisco patches exploited Secure Email Gateway RCE

Published: 2026-10-15 · Severity: high · Sectors: technology
Canonical: https://vorant.io/reports/5527fab2-82be-52c9-8b3c-66e842bd6b11/cisco-patches-exploited-secure-email-gateway-rce

> CERT-FR warns CVE-2026-76519, an actively exploited remote code execution flaw in Cisco AsyncOS for Secure Email Gateway, requires urgent patching.

CERT-FR issued an advisory regarding a vulnerability in Cisco AsyncOS Software for Secure Email Gateway (CVE-2026-76519) that allows an attacker to achieve remote code execution and compromise data integrity. Cisco has confirmed that this vulnerability is being actively exploited in the wild, making it a priority patching item for affected organizations.

The vulnerability affects AsyncOS Software for Secure Email Gateway versions 15.5.x prior to 15.5.5-014 and versions 16.x prior to 16.5.0-780. Defenders running these versions should consult Cisco's security advisory (cisco-sa-esa-afw-zqYJkjxp, published October 14, 2026) and apply the available patches immediately given the confirmed active exploitation.

No further technical details on the exploitation method, threat actor attribution, or indicators of compromise were provided in this advisory. Organizations using Cisco Secure Email Gateway should prioritize patching and monitor for anomalous activity on affected systems.

## Mentioned in this report

- Vulnerabilities: CVE-2026-76519 (KEV)

Source reporting: https://www.cert.ssi.gouv.fr/avis/CERTFR-2026-AVI-1325

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