Vulnerability Monitor

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CVE-2021-1236


Multiple Cisco products are affected by a vulnerability in the Snort application detection engine that could allow an unauthenticated, remote attacker to bypass the configured policies on an affected system. The vulnerability is due to a flaw in the detection algorithm. An attacker could exploit this vulnerability by sending crafted packets that would flow through an affected system. A successful exploit could allow the attacker to bypass the configured policies and deliver a malicious payload to the protected network.


Security Impact Summary

This vulnerability carries a MEDIUM severity rating with a CVSS v3.1 score of 5.3, indicating it can be exploited remotely over the network with relatively low complexity without requiring user interaction and does not require pre-existing privileges . The vulnerability impacts limited integrity, for affected systems. Impacting 19 products from cisco, from cisco, from cisco and 16 others, organizations running these solutions should prioritize assessment and patching.

Historical Context

Reported in 2021, this vulnerability emerged during an era marked by increased sophistication in supply chain attacks, cloud infrastructure vulnerabilities, and software-as-a-service (SaaS) security challenges. Security practices during this period emphasized zero-trust architectures, container security, and API protection.


Published

2021-01-13T22:15:20.583

Last Modified

2024-11-26T16:09:02.407

Status

Modified

Source

[email protected]

Severity

CVSSv3.1: 5.3 (MEDIUM)

CVSSv2 Vector

AV:N/AC:L/Au:N/C:N/I:P/A:N

  • Access Vector: NETWORK
  • Access Complexity: LOW
  • Authentication: NONE
  • Confidentiality Impact: NONE
  • Integrity Impact: PARTIAL
  • Availability Impact: NONE
Exploitability Score

10.0

Impact Score

2.9

Weaknesses
  • Type: Secondary
    CWE-670
  • Type: Primary
    CWE-670

Affected Vendors & Products
Type Vendor Product Version/Range Vulnerable?
Operating System cisco ios_xe < 17.4.1 Yes
Hardware cisco 1100-4p_integrated_services_router - No
Hardware cisco 1100-8p_integrated_services_router - No
Hardware cisco 1101-4p_integrated_services_router - No
Hardware cisco 1109-2p_integrated_services_router - No
Hardware cisco 1109-4p_integrated_services_router - No
Hardware cisco 1111x-8p_integrated_services_router - No
Hardware cisco 4221_integrated_services_router - No
Hardware cisco 4321_integrated_services_router - No
Hardware cisco 4331_integrated_services_router - No
Hardware cisco 4351_integrated_services_router - No
Hardware cisco 4431_integrated_services_router - No
Hardware cisco 4451-x_integrated_services_router - No
Hardware cisco 4461_integrated_services_router - No
Hardware cisco csr_1000v - No
Hardware cisco isa_3000 - No
Application cisco firepower_threat_defense < 6.5.0.5 Yes
Application cisco secure_firewall_management_center 2.9.14.0 Yes
Application cisco secure_firewall_management_center 2.9.14.14 Yes
Application cisco secure_firewall_management_center 2.9.15 Yes
Application cisco secure_firewall_management_center 2.9.16 Yes
Application cisco secure_firewall_management_center 2.9.17 Yes
Application snort snort < 2.9.14 Yes

References

How SecUtils Interprets This CVE

SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For cisco's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.