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

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-20179— Multiple Cisco Products Snort 3 Generic Routing Encapsulation Denial of Service Vulnerabilities

Quick assessment

Affected
Cisco Cisco Open Source Snort3
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.

思科多款产品受到 Snort 3 通用路由封装（GRE）检测引擎中一处漏洞的影响。该漏洞可能允许未认证的远程攻击者导致 Snort 3 检测引擎重启，从而中断数据包检测服务。 该漏洞源于 Snort 3 在解析 GRE 数据包时错误检查不完整。攻击者可通过向目标设备发送特制的 GRE 数据包（由 Snort 进行解析）来利用此漏洞。一旦利用成功，攻击者可导致 Snort 3 检测引擎意外重启，进而引发拒绝服务（DoS）状态。

CVSS 5.8 · Medium

Possible ATT&CK Techniques 1 AI

T1499.003 · Application Exhaustion Flood

Affected Version Matrix 203

VendorProduct Version RangeStatus
Cisco Cisco Open Source Snort3 3.12.2.0 affected
3.1.2.0 affected
3.1.3.0 affected
3.1.4.0 affected
3.1.5.0 affected
3.1.6.0 affected
3.1.7.0 affected
3.1.8.0 affected
… +97 more rows
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
… +52 more rows
Cisco Cisco UTD SNORT IPS Engine Software 17.12.1a affected
17.12.2 affected
17.13.1a affected
17.12.3 affected
17.14.1a affected
17.12.4 affected
17.12.3a affected
17.15.1a affected
… +30 more rows
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-20179

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Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.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
Multiple Cisco Products Snort 3 Generic Routing Encapsulation Denial of Service Vulnerabilities
Source: CVE Program / CVE List V5
Vulnerability Description
Multiple Cisco products are affected by a vulnerability in the Snort 3 Generic Routing Encapsulation (GRE) Detection Engine that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to restart, resulting in an interruption of packet inspection. This vulnerability is due to incomplete error checking when Snort 3 parses GRE packets. An attacker could exploit this vulnerability by sending a crafted GRE packet to a targeted device to be parsed by Snort. A successful exploit could allow the attacker to cause the Snort 3 Detection Engine to restart unexpectedly, resulting in a 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
超界折返处理错误
Source: CVE Program / CVE List V5

Affected Products

Vendor Product Affected Versions CPE Subscribe
Cisco Cisco Open Source Snort3 3.12.2.0 -
Cisco Cisco Secure Firewall Threat Defense (FTD) Software 7.0.0 -
Cisco Cisco UTD SNORT IPS Engine Software 17.12.1a -

II. Public POCs for CVE-2026-20179

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

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-20179

请登录查看更多情报信息。

Other References for CVE-2026-20179 (1)

Same Patch Batch · Cisco · 2026-10-21 · 34 CVEs total

CVE-2026-76466 9.8 CRITICAL Cisco Expressway Series Remote Code Execution Vulnerability
CVE-2026-76473 9.8 CRITICAL Cisco Unified Communications Products Hardening Release: October 2026 - Improper control o
CVE-2026-76474 9.8 CRITICAL Cisco Unified Communications Products Hardening Release: October 2026 - Improper Authentic
CVE-2026-76475 9.3 CRITICAL Cisco Unified Communications Products Hardening Release: October 2026 - Cross-site Scripti
CVE-2026-20043 9.0 CRITICAL Multiple Cisco Products Snort 3 Software Hardening Release: October 2026
CVE-2026-76477 8.8 HIGH Cisco Unified Communications Products Hardening Release: October 2026 - Injection Vulnerab
CVE-2026-76476 8.8 HIGH Cisco Unified Communications Products Hardening Release: October 2026 - Improper Input Val
CVE-2026-76478 8.8 HIGH Cisco Unified Communications Products Hardening Release: October 2026 - Improper Access Co
CVE-2026-76490 8.6 HIGH Cisco Expressway Series Software Hardening Release: October 2026 - Out-of-bounds Write Vul
CVE-2026-76524 7.8 HIGH Open Source Snort 3 Control Channel Socket Aribitrary Command Execution Vulnerability
CVE-2026-20291 7.8 HIGH Multiple Cisco Products Snort 3 Software Hardening Release: October 2026
CVE-2026-76479 7.8 HIGH Cisco Unified Communications Products Hardening Release: October 2026 - Path Traversal Vul
CVE-2026-76494 7.8 HIGH Cisco Expressway Series Software Hardening Release: October 2026 - Code Injection Vulnerab
CVE-2026-76495 7.8 HIGH Cisco Expressway Series Software Hardening Release: October 2026 - Incorrect Permission As
CVE-2026-76481 7.5 HIGH Cisco Unified Communications Products Hardening Release: October 2026 - Improper Check or
CVE-2026-76491 7.5 HIGH Cisco Expressway Series Software Hardening Release: October 2026 - Denial of Service Vulne
CVE-2026-76492 7.5 HIGH Cisco Expressway Series Software Hardening Release: October 2026 - NULL Pointer Vulnerabil
CVE-2026-76505 7.5 HIGH Cisco IOS XR Software for ASR 9000 Series Routers IPv4 Unicast Packets Denial of Service V
CVE-2026-76493 7.5 HIGH Cisco Expressway Series Software Hardening Release: October 2026 - Uncaught Exception Vuln
CVE-2026-20236 7.5 HIGH Multiple Cisco Products Snort 3 Software Hardening Release: October 2026

Showing top 20 of 34 CVEs. View all on vendor page → →

IV. Related Vulnerabilities

Same product: Cisco Open Source Snort3
Same vendor: Cisco
Same weakness: CWE-128

V. Comments for CVE-2026-20179

No comments yet

Leave a comment