CVE-2021-34783— Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Software-Based SSL/TLS Denial of Service Vulnerability
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I. Basic Information for CVE-2021-34783
Vulnerability Information
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Vulnerability Title
Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Software-Based SSL/TLS Denial of Service Vulnerability
Source: NVD (National Vulnerability Database)
Vulnerability Description
A vulnerability in the software-based SSL/TLS message handler of Cisco Adaptive Security Appliance (ASA) Software and Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. This vulnerability is due to insufficient validation of SSL/TLS messages when the device performs software-based SSL/TLS decryption. An attacker could exploit this vulnerability by sending a crafted SSL/TLS message to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. Note: Datagram TLS (DTLS) messages cannot be used to exploit this vulnerability.
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
内存缓冲区边界内操作的限制不恰当
Source: NVD (National Vulnerability Database)
Vulnerability Title
Cisco Firepower Threat Defense和Cisco Adaptive Security Appliances Software 输入验证错误漏洞
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）和Cisco Adaptive Security Appliances Software（ASA Software） 存在输入验证错误漏洞，该漏洞源于设备在进行基于软件的SSL TLS解密时，对SSL TLS消息验证不足造成的。攻击者可利用该漏洞导致受影响的设备重新加载，从而导致拒绝服务(DoS)条件
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 Adaptive Security Appliance (ASA) Software | n/a | - |
II. Public POCs for CVE-2021-34783
| # | POC Description | Source Link | Shenlong Link |
|---|
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- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-tls-decrypt-dos-BMxYjm8Mvendor-advisoryx_refsource_CISCO
- https://nvd.nist.gov/vuln/detail/CVE-2021-34783
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-2021-40116 | 8.6 HIGH | Multiple Cisco Products Snort Rule Denial of Service Vulnerability |
| CVE-2021-40118 | 8.6 HIGH | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Servi |
| CVE-2021-34793 | 8.6 HIGH | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Transpare |
| CVE-2021-34792 | 8.6 HIGH | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Resource |
| CVE-2021-34781 | 8.6 HIGH | Cisco Firepower Threat Defense Software SSH Connections Denial of Service Vulnerability |
| 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-2021-34755 | 6.7 MEDIUM | Cisco Firepower Threat Defense Software Command Injection Vulnerabilities |
| CVE-2021-34756 | 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-2021-40125 | 5.3 MEDIUM | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software IKEv2 Sit |
| CVE-2021-34787 | 5.3 MEDIUM | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Identity- |
| CVE-2021-34794 | 5.3 MEDIUM | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software SNMP Acce |
| CVE-2021-34763 | 4.8 MEDIUM | Cisco Firepower Management Center Software Cross-Site Scripting and Open Redirect Vulnerab |
| CVE-2021-34764 | 4.8 MEDIUM | Cisco Firepower Management Center Software Cross-Site Scripting and Open Redirect Vulnerab |
| CVE-2021-34790 | 4.7 MEDIUM | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Applicati |
| CVE-2021-34791 | 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 |
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V. Comments for CVE-2021-34783
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