Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1336 CNY

100%
Buy Us a Coffee

CVE-2026-20290— Cisco Secure Firewall Threat Defense Software Snort 2 SSL/TLS Denial of Service Vulnerability

Quick assessment

Affected
Cisco Cisco Secure Firewall Threat Defense (FTD) Software
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

Cisco Secure Firewall Threat Defense（FTD）软件中 Snort 2 检测引擎在解析 SSL/TLS 证书时存在漏洞，可能允许经过身份验证的远程攻击者导致 Snort 2 检测引擎重启。 该漏洞是由于对 SSL 证书的校验不完整所致。攻击者可以通过发送精心构造的 SSL 连接建立请求，使其被 Snort 2 解析，从而利用此漏洞。成功利用该漏洞后，攻击者可能使 Snort 2 检测引擎意外重启，导致拒绝服务（DoS）状态。

CVSS 5.8 · Medium EPSS 0.19% · P9

Possible ATT&CK Techniques 1 AI

T1499 · Endpoint Denial of Service

Affected Version Matrix 55

VendorProduct Version RangeStatus
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.0.0 affected
7.0.0.1 affected
7.0.1 affected
7.0.1.1 affected
7.0.2 affected
7.2.0 affected
7.0.2.1 affected
7.0.3 affected
… +47 more rows
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-20290

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
Cisco Secure Firewall Threat Defense Software Snort 2 SSL/TLS Denial of Service Vulnerability
Source: CVE Program / CVE List V5
Vulnerability Description
A vulnerability in SSL/TLS certificate parsing in the Snort 2 Detection Engine of Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the Snort 2 Detection Engine to restart. This vulnerability is due to incomplete validation of the SSL certificate. An attacker could exploit this vulnerability by sending a crafted SSL connection setup request to be parsed by Snort 2. A successful exploit could allow the attacker to cause the Snort 2 Detection Engine to restart unexpectedly, resulting in a denial of service (DoS) condition.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L
Source: CVE Program / CVE List V5
Vulnerability Type
使用不正确的长度值访问缓冲区
Source: CVE Program / CVE List V5

Affected Products

Vendor Product Affected Versions CPE Subscribe
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.0.0 -

II. Public POCs for CVE-2026-20290

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-20290

请登录查看更多情报信息。

Vendor Advisories for CVE-2026-20290 (1)

Same Patch Batch · Cisco · 2026-09-16 · 79 CVEs total

CVE-2026-20192 10.0 CRITICAL Cisco Identity Services Engine Hardening Release - Access Control Vulnerabilities
CVE-2026-76460 10.0 CRITICAL Cisco Identity Services Engine Authentication Bypass Vulnerability
CVE-2026-76423 10.0 CRITICAL Cisco ISE API Authentication Bypass Vulnerability
CVE-2026-20130 10.0 CRITICAL Cisco Identity Services Engine Hardening Release - Improper Neutralization Vulnerabilities
CVE-2026-20332 9.9 CRITICAL Cisco Secure Adaptive Security Appliance Software, Secure Firewall Threat Defense Software
CVE-2026-20307 9.9 CRITICAL Cisco Identity Services Engine Remote Code Execution Vulnerability
CVE-2026-20234 9.9 CRITICAL Cisco Identity Services Engine Hardening Release - Insuffiencently Protected Credential Vu
CVE-2026-20324 9.9 CRITICAL Cisco Secure Firewall Management Center sftunnel Root Arbitrary Code Exectution Vulnerabil
CVE-2026-20325 9.9 CRITICAL Cisco Nexus Dashboard Software Security Hardening Release September 2026 - Improper Neutra
CVE-2026-20329 9.9 CRITICAL Cisco Secure Adaptive Security Appliance Software, Secure Firewall Threat Defense Software
CVE-2026-20322 9.9 CRITICAL Cisco Nexus Dashboard Software Security Hardening Release September 2026 - Improper Access
CVE-2026-20330 9.9 CRITICAL Cisco Secure Adaptive Security Appliance Software, Secure Firewall Threat Defense Software
CVE-2026-20242 9.8 CRITICAL Cisco Secure Firewall Management Center Software Java Deserialization Remote Code Executio
CVE-2026-20326 9.8 CRITICAL Cisco Nexus Dashboard Software Security Hardening Release September 2026 - Missing Authent
CVE-2026-20331 9.6 CRITICAL Cisco Secure Adaptive Security Appliance Software, Secure Firewall Threat Defense Software
CVE-2026-20306 9.1 CRITICAL Cisco Identity Services Engine Command Injection Vulnerability
CVE-2026-20211 9.1 CRITICAL Cisco Identity Services Engine Remote Code Execution Vulnerability
CVE-2026-20341 9.1 CRITICAL Cisco Secure Firewall Management Center Software sftunnel Deserialization Root Command Exe
CVE-2026-20176 9.1 CRITICAL Cisco Identity Services Engine Remote Code Execution Vulnerability
CVE-2026-20284 9.1 CRITICAL Cisco Identity Search Engine SXP REST API SQL Injection Vulnerability

Showing top 20 of 79 CVEs. View all on vendor page → →

IV. Related Vulnerabilities

Same product: Cisco Secure Firewall Threat Defense (FTD) Software
Same vendor: Cisco
Same weakness: CWE-805

V. Comments for CVE-2026-20290

No comments yet

Leave a comment