Snort
CVE-2021-40114
HIGH
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A06:2025 - Insecure Design
ASVS 5.0
V2 - Validation and Business Logic Resource allocation limits
MITRE ATT&CK
1 technique across 1 tactic: Impact The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 7.5 (HIGH). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. |
| Exploit ScenarioDerived | A remote attacker could exhaust system resources through uncontrolled allocation by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability. |
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Alert meAnalysisAI
Multiple Cisco products are affected by a vulnerability in the way the Snort detection engine processes ICMP traffic that could allow an unauthenticated, remote attacker to cause a denial of service. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Set resource limits, implement rate limiting, validate input sizes.
Affects your stack
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Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
This vulnerability is classified as Allocation of Resources Without Limits (CWE-770), which allows attackers to exhaust system resources through uncontrolled allocation. Multiple Cisco products are affected by a vulnerability in the way the Snort detection engine processes ICMP traffic 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 memory resource management while the Snort detection engine is processing ICMP packets. An attacker could exploit this vulnerability by sending a series of ICMP packets through an affected device. A successful exploit could allow the attacker to exhaust resources on the affected device, causing the device to reload. Affected products include: Cisco Firepower Threat Defense, Cisco Secure Firewall Management Center, Cisco Unified Threat Defense, Snort.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
Multiple Cisco products are affected by a vulnerability in the way the Snort detection engine processes ICMP traffic 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 memory resource management while the Snort detection engine is processing ICMP packets. An attacker could exploit this vulnerability by sending a series of ICMP packets through an affected device. A successful exploit could allow the attacker to exhaust resources on the affected device, causing the device to reload.
Threat Intelligence Overview
NVD
CVE.org
EPSS
VulDB
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.
Affected Products (CPE)NVD
Untrusted search path vulnerability in Snort 2.9.7.0-WIN32 allows remote attackers to execute arbitrary code and conduct
A buffer under-read in the Snort 3 HTTP decoder lets unauthenticated, remote attackers crash the detection engine or exp
Multiple Cisco products are affected by a vulnerability in the rate filtering feature of the Snort detection engine that
Multiple Cisco products are affected by a vulnerability in the Snort detection engine that could allow an unauthenticate
Multiple Cisco products are affected by a vulnerability in Snort rules that could allow an unauthenticated, remote attac
Cisco Sourcefire Snort 3.0 before build 233 mishandles Ether Type Validation. Rated high severity (CVSS 7.5), this vulne
Multiple Cisco products are affected by a vulnerability in the Snort detection engine that could allow an unauthenticate
Denial of service in Cisco Snort 3 allows unauthenticated remote attackers to force the detection engine to restart by s
Multiple Cisco products are affected by a vulnerability in the Snort Intrusion Prevention System (IPS) rule engine that
Cisco Snort 3 Detection Engine can be remotely restarted by an unauthenticated attacker through crafted HTTP packets exp
Unauthenticated remote attackers can crash the Snort 3 Detection Engine by sending crafted HTTP packets with malformed M
Snort 3 Detection Engine crashes when processing malformed VBA data due to improper decompression error handling, allowi
GitHub PoC
Exploit-DB