TIRESIS/Forecast/CVE-2026-76519
⚡ CISA KEV — Actively ExploitedHIGH RISK

CVE-2026-76519

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 …

SMB Attack Probability Score
66/100high
Weighted: EPSS · CISA KEV · SMB stack prevalence · exploit maturity · CVSS vector
CVSS v3
9.8
EPSS (30d)
1.74%
SMB Exposure
42.5/100
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
🔓
SMB Impact
How this vulnerability affects a real small business
1
How this breaks an SMB

Firewall or VPN compromise gives attackers full internal network access — no further credentials needed. All connected systems are immediately at risk.

2
Typical real-world scenario

Automated scanner identifies the exposed appliance. Within hours, lateral movement begins: file servers, domain controller, and backup systems are reached.

3
Estimated downtime & cost
Est. downtime
3–7 days
Business cost range
€15K–€80K
4
What IT should check this week
Is this appliance directly internet-facing?
Is firmware/OS version patched to latest?
Are admin consoles accessible without MFA?
Is network segmentation between IT and OT/servers active?
Scenarios are generated based on software category and CVE characteristics. Cost ranges reflect SMB incidents in TIRESIS incident database.
Threat Evolution Timeline
From disclosure to predicted exploitation — 6 events
◈ 1 predicted
📋
14 Oct 2026
Vulnerability disclosed
CVE published by NVD with CVSS 9.8 (CRITICAL)
🚨
14 Oct 2026CISA KEV
Added to CISA KEV catalog
CISA confirms active exploitation. Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
⚡
16 Oct 2026
Exploit in the wild
Active exploitation observed — automated scanning and targeted attacks underway
🔬
28 Oct 2026
Proof-of-Concept published
Public PoC code available — exploitation now accessible to non-expert attackers
📍
TODAY
Today
EPSS: 1.7% probability of exploitation in next 30 days. SMB Risk Score: 66/100
Forecast →
✅
28 Dec 2026◈ predicted · in 60 days
Predicted: widespread patch adoption
Low EPSS suggests limited active exploitation. Most organizations expected to patch in routine maintenance cycle.
◈ Predicted eventsare estimates based on EPSS score, exploit maturity, and historical CVE progression patterns. They are not guaranteed outcomes.
Affected Products
secure email gateway virtual appliance c300vsecure email gateway virtual appliance c600vasyncossecure email gateway virtual appliance c100vsecure email gateway c195secure email gateway c395secure email gateway c695
Remediation & References
⚡ CISA Required Action

Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

Federal agency patch deadline: 2026-10-17
What to do
🚨Patch immediately — actively exploited in the wildcritical

CISA has confirmed exploitation of this vulnerability. Federal agencies must patch within the KEV deadline. SMBs should treat this as P0: patch or mitigate within 24–48 hours.

🌐No authentication required — restrict external access nowhigh

This vulnerability can be exploited remotely without credentials or user interaction. Until patched: block access to the affected service from the internet using firewall rules or ACLs. Only allow access from trusted IPs.

Official Patch & Advisory Sources
NVD Full Entry ↗Official vulnerability detail, CVSS vectors, CPE listCISA KEV Entry ↗CISA Known Exploited Vulnerabilities catalogEPSS Score ↗Exploit Prediction Scoring System — FIRST.orgMitre CVE ↗MITRE CVE Program official entry
Vendor & Exploit References
Scoring Methodology

SMB Attack Probability Score weights: EPSS exploit likelihood (35%), CISA KEV active exploitation (25%), SMB stack prevalence (20%), exploit maturity (10%), CVSS network vector complexity (10%). Impact scenarios are derived from software category and historical SMB incident patterns. Scores recompute daily.

undefined — SMB Risk & Business Impact — TIRESIS — Tiresis