CVE-2021-34741— Cisco Email Security Appliance Denial of Service Vulnerability
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I. Basic Information for CVE-2021-34741
Vulnerability Information
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Vulnerability Title
Cisco Email Security Appliance Denial of Service Vulnerability
Source: NVD (National Vulnerability Database)
Vulnerability Description
A vulnerability in the email scanning algorithm of Cisco AsyncOS software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to perform a denial of service (DoS) attack against an affected device. This vulnerability is due to insufficient input validation of incoming emails. An attacker could exploit this vulnerability by sending a crafted email through Cisco ESA. A successful exploit could allow the attacker to exhaust all the available CPU resources on an affected device for an extended period of time, preventing other emails from being processed and resulting in a DoS condition.
Source: NVD (National Vulnerability Database)
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Source: NVD (National Vulnerability Database)
Vulnerability Type
不加限制或调节的资源分配
Source: NVD (National Vulnerability Database)
Vulnerability Title
Cisco Email Security Appliance 输入验证错误漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Cisco Email Security Appliance（ESA）是美国思科（Cisco）公司的一个电子邮件安全设备。 Cisco Email Security Appliance 存在输入验证错误漏洞，该漏洞源于传入邮件的输入验证不足造成的。攻击者可利用该漏洞对受影响的设备执行拒绝服务(DoS)攻击。
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 Email Security Appliance (ESA) | n/a | - |
II. Public POCs for CVE-2021-34741
| # | POC Description | Source Link | Shenlong Link |
|---|
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- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-esa-dos-JOm9ETfOvendor-advisoryx_refsource_CISCO
- https://nvd.nist.gov/vuln/detail/CVE-2021-34741
Same Patch Batch · Cisco · 2021-11-04 · 18 CVEs total
| CVE-2021-34795 | 10.0 CRITICAL | Cisco Catalyst PON Series Switches Optical Network Terminal Vulnerabilities |
| CVE-2021-40112 | 10.0 CRITICAL | Cisco Catalyst PON Series Switches Optical Network Terminal Vulnerabilities |
| CVE-2021-40113 | 10.0 CRITICAL | Cisco Catalyst PON Series Switches Optical Network Terminal Vulnerabilities |
| CVE-2021-40119 | 9.8 CRITICAL | Cisco Policy Suite Static SSH Keys Vulnerability |
| CVE-2021-34739 | 8.1 HIGH | Cisco Small Business Series Switches Session Credentials Replay Vulnerability |
| CVE-2021-40124 | 6.7 MEDIUM | Cisco AnyConnect Secure Mobility Client for Windows with Network Access Manager Module Pri |
| CVE-2021-34773 | 6.5 MEDIUM | Cisco Unified Communications Products Cross-Site Request Forgery Vulnerability |
| CVE-2021-40120 | 6.5 MEDIUM | Cisco Small Business RV Series Routers Command Injection Vulnerability |
| CVE-2021-40115 | 6.1 MEDIUM | Cisco Webex Video Mesh Cross-Site Scripting Vulnerability |
| CVE-2021-1500 | 5.4 MEDIUM | Cisco Webex Video Mesh Arbitrary Site Redirection Vulnerability |
| CVE-2021-34784 | 5.4 MEDIUM | Cisco Prime Infrastructure and Evolved Programmable Network Manager Stored Cross-Site Scri |
| CVE-2021-40128 | 5.3 MEDIUM | Cisco Webex Meetings Email Content Injection Vulnerability |
| CVE-2021-40127 | 5.3 MEDIUM | Cisco Small Business 200, 300, and 500 Series Switches Web-Based Management Interface Deni |
| CVE-2021-34774 | 4.9 MEDIUM | Cisco Common Services Platform Collector Information Disclosure Vulnerability |
| CVE-2021-34731 | 4.8 MEDIUM | Cisco Prime Access Registrar Stored Cross-Site Scripting Vulnerability |
| CVE-2021-40126 | 4.3 MEDIUM | Cisco Umbrella Email Enumeration Vulnerability |
| CVE-2021-34701 | 4.3 MEDIUM | Cisco Unified Communications Products Path Traversal Vulnerability |
IV. Related Vulnerabilities
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Same weakness: CWE-770
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V. Comments for CVE-2021-34741
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