CVE-2021-1495— Multiple Cisco Products Snort HTTP Detection Engine File Policy Bypass Vulnerability
Quick assessment
Affected
Cisco Cisco Firepower Threat Defense 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 Firepower Threat Defense（FTD）是美国思科（Cisco）公司的一套提供下一代防火墙服务的统一软件。 Cisco Firepower Threat Defense (FTD 存在安全特征问题漏洞，该漏洞源于对特定HTTP标头参数的不正确处理导致的。远程攻击者可以发送特制的HTTP数据包，以绕过针对HTTP数据包配置的文件策略，并传递恶意负载。以下产品及版本受到影响：Cisco Firepower Threat Defense (FTD): 6.2.2, 6.2.3, 6
Possible ATT&CK Techniques 3 AI
T1059 · Command and Scripting Interpreter T1071.001 · Web Protocols T1190 · Exploit Public-Facing Application
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I. Basic Information for CVE-2021-1495
Vulnerability Information
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Vulnerability Title
Multiple Cisco Products Snort HTTP Detection Engine File Policy Bypass Vulnerability
Source: CVE Program / CVE List V5
Vulnerability Description
Multiple Cisco products are affected by a vulnerability in the Snort detection engine that could allow an unauthenticated, remote attacker to bypass a configured file policy for HTTP. The vulnerability is due to incorrect handling of specific HTTP header parameters. An attacker could exploit this vulnerability by sending crafted HTTP packets through an affected device. A successful exploit could allow the attacker to bypass a configured file policy for HTTP packets and deliver a malicious payload.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
Source: CVE Program / CVE List V5
Vulnerability Type
N/A
Source: CVE Program / CVE List V5
Vulnerability Title
Cisco Firepower Threat Defense 安全特征问题漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Cisco Firepower Threat Defense（FTD）是美国思科（Cisco）公司的一套提供下一代防火墙服务的统一软件。 Cisco Firepower Threat Defense (FTD 存在安全特征问题漏洞，该漏洞源于对特定HTTP标头参数的不正确处理导致的。远程攻击者可以发送特制的HTTP数据包，以绕过针对HTTP数据包配置的文件策略，并传递恶意负载。以下产品及版本受到影响：Cisco Firepower Threat Defense (FTD): 6.2.2, 6.2.3, 6
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-2021-1495
| # | POC Description | Source Link | Shenlong Link |
|---|
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Vendor Advisories for CVE-2021-1495 (1)
Mailing List Discussions for CVE-2021-1495 (1)
Same Patch Batch · Cisco · 2021-04-29 · 17 CVEs total
| CVE-2021-1445 | 8.6 HIGH | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Servi |
| CVE-2021-1501 | 8.6 HIGH | Cisco Adaptive Security Appliance Software and Cisco Firepower Threat Defense Software SIP |
| CVE-2021-1504 | 8.6 HIGH | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Servi |
| CVE-2021-1493 | 8.5 HIGH | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Servi |
| CVE-2021-1476 | 6.7 MEDIUM | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Command I |
| CVE-2021-1488 | 6.7 MEDIUM | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software for Firep |
| CVE-2021-1256 | 6.0 MEDIUM | Cisco Firepower Threat Defense Software Command File Overwrite Vulnerability |
| CVE-2021-1369 | 5.4 MEDIUM | Cisco Firepower Device Manager On-Box Software XML External Entity Vulnerability |
| CVE-2021-1456 | 4.8 MEDIUM | Cisco Firepower Management Center Software Cross-Site Scripting Vulnerabilities |
| CVE-2021-1457 | 4.8 MEDIUM | Cisco Firepower Management Center Software Cross-Site Scripting Vulnerabilities |
| CVE-2021-1458 | 4.8 MEDIUM | Cisco Firepower Management Center Software Cross-Site Scripting Vulnerabilities |
| CVE-2021-1477 | 4.3 MEDIUM | Cisco Firepower Management Center Software Policy Vulnerability |
| CVE-2021-1402 | Cisco Firepower Threat Defense Software SSL Decryption Policy Denial of Service Vulnerabil | |
| CVE-2021-1448 | Cisco Firepower Threat Defense Software Command Injection Vulnerability | |
| CVE-2021-1455 | Cisco Firepower Management Center Software Cross-Site Scripting Vulnerabilities | |
| CVE-2021-1489 | Cisco Firepower Device Manager Software Filesystem Space Exhaustion Denial of Service Vuln |
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V. Comments for CVE-2021-1495
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