CVE-2021-40116— Multiple Cisco Products Snort Rule Denial of Service Vulnerability
Get alerts for future matching vulnerabilitiesLog in to subscribe
I. Basic Information for CVE-2021-40116
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View Shenlong Deep Dive ↗ Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.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 Rule Denial of Service Vulnerability
Source: NVD (National Vulnerability Database)
Vulnerability Description
Multiple Cisco products are affected by a vulnerability in Snort rules that could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device.The vulnerability is due to improper handling of the Block with Reset or Interactive Block with Reset actions if a rule is configured without proper constraints. An attacker could exploit this vulnerability by sending a crafted IP packet to the affected device. A successful exploit could allow the attacker to cause through traffic to be dropped. Note: Only products with Snort3 configured and either a rule with Block with Reset or Interactive Block with Reset actions configured are vulnerable. Products configured with Snort2 are not vulnerable.
Source: NVD (National Vulnerability Database)
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Source: NVD (National Vulnerability Database)
Vulnerability Type
非预期数据类型处理不恰当
Source: NVD (National Vulnerability Database)
Vulnerability Title
Cisco Products Snort 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Cisco Products Snort是美国思科（Cisco）公司的一个用于思科产品的Snort引擎。 Cisco Products Snort Rule 存在安全漏洞，该漏洞源于在没有适当约束的情况下配置规则时，对Block with Reset或Interactive Block with Reset操作的不当处理造成的。攻击者可以通过向受影响的设备发送精心设计的 IP 数据包来利用此漏洞。成功的利用可能允许攻击者导致直通流量被丢弃。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)
Affected Products
| Vendor | Product | Affected Versions | CPE | Subscribe |
|---|---|---|---|---|
| Cisco | Cisco Firepower Threat Defense Software | n/a | - |
II. Public POCs for CVE-2021-40116
| # | POC Description | Source Link | Shenlong Link |
|---|
AI-Generated POCPremium
No public POC found.
Login to generate AI POCIII. Intelligence Information for CVE-2021-40116
请登录查看更多情报信息。
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-snort-dos-RywH7ezMvendor-advisoryx_refsource_CISCO
- https://nvd.nist.gov/vuln/detail/CVE-2021-40116
Same Patch Batch · Cisco · 2021-10-27 · 20 CVEs total
| CVE-2021-40117 | 8.6 HIGH | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software SSL/TLS D |
| CVE-2021-34781 | 8.6 HIGH | Cisco Firepower Threat Defense Software SSH Connections Denial of Service Vulnerability |
| CVE-2021-34783 | 8.6 HIGH | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Software- |
| CVE-2021-34792 | 8.6 HIGH | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Resource |
| CVE-2021-34793 | 8.6 HIGH | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Transpare |
| CVE-2021-40118 | 8.6 HIGH | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Servi |
| CVE-2021-34762 | 8.1 HIGH | Cisco Firepower Management Center Software Authenticated Directory Traversal Vulnerability |
| CVE-2021-40114 | 6.8 MEDIUM | Multiple Cisco Products Snort Memory Leak Denial of Service Vulnerability |
| CVE-2021-34756 | 6.7 MEDIUM | Cisco Firepower Threat Defense Software Command Injection Vulnerabilities |
| CVE-2021-34755 | 6.7 MEDIUM | Cisco Firepower Threat Defense Software Command Injection Vulnerabilities |
| CVE-2021-34754 | 5.8 MEDIUM | Cisco Firepower Threat Defense Software Ethernet Industrial Protocol Policy Bypass Vulnera |
| CVE-2021-34794 | 5.3 MEDIUM | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software SNMP Acce |
| CVE-2021-34787 | 5.3 MEDIUM | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Identity- |
| CVE-2021-40125 | 5.3 MEDIUM | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software IKEv2 Sit |
| CVE-2021-34764 | 4.8 MEDIUM | Cisco Firepower Management Center Software Cross-Site Scripting and Open Redirect Vulnerab |
| CVE-2021-34763 | 4.8 MEDIUM | Cisco Firepower Management Center Software Cross-Site Scripting and Open Redirect Vulnerab |
| CVE-2021-34791 | 4.7 MEDIUM | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Applicati |
| CVE-2021-34790 | 4.7 MEDIUM | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Applicati |
| CVE-2021-34761 | 4.4 MEDIUM | Cisco Firepower Threat Defense Software CLI Arbitrary File Write Vulnerability |
IV. Related Vulnerabilities
Same product: Cisco Firepower Threat Defense Software
- CVE-2025-20268
Cisco Secure Firewall Threat Defense Software Geolocation Re - CVE-2025-20222
Cisco Adaptive Security Appliance Software and Firepower Thr - CVE-2025-20217
Cisco Firepower Threat Defense Intrusion Detection Denial of - CVE-2021-1494
Snort 安全漏洞 - CVE-2021-34753
Cisco Firepower Threat Defense Ethernet Industrial Protocol
Same vendor: Cisco
- CVE-2026-20219
Cisco Slido 安全漏洞 - CVE-2026-20034
Cisco Unity Connection Remote Code Execution Vulnerability - CVE-2026-20035
Cisco Unity Connection Server-Side Request Forgery Vulnerabi - CVE-2026-20167
Cisco IoT Field Network Director Remote Device Denial of Ser - CVE-2026-20169
Cisco IoT Field Network Director Command Injection Vulnerabi
Same weakness: CWE-241
- CVE-2025-66550
Nextcloud Calendar attachments of local files are offered to - CVE-2024-21935
AMD Instinct MI300X accelerators 安全漏洞 - CVE-2024-21927
AMD Instinct MI300X accelerators 安全漏洞 - CVE-2025-7339
on-headers vulnerable to http response header manipulation - CVE-2025-2268
HP LaserJet MFP M232-M237 Printer Series - Potential Denial
V. Comments for CVE-2021-40116
No comments yet