CVE-2021-1616— Cisco IOS XE Software H.323 Application Level Gateway Bypass Vulnerability
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I. Basic Information for CVE-2021-1616
Vulnerability Information
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Vulnerability Title
Cisco IOS XE Software H.323 Application Level Gateway Bypass Vulnerability
Source: NVD (National Vulnerability Database)
Vulnerability Description
A vulnerability in the H.323 application level gateway (ALG) used by the Network Address Translation (NAT) feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to bypass the ALG. This vulnerability is due to insufficient data validation of traffic that is traversing the ALG. An attacker could exploit this vulnerability by sending crafted traffic to a targeted device. A successful exploit could allow the attacker to bypass the ALG and open connections that should not be allowed to a remote device located behind the ALG. Note: This vulnerability has been publicly discussed as NAT Slipstreaming.
Source: NVD (National Vulnerability Database)
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N
Source: NVD (National Vulnerability Database)
Vulnerability Type
保护机制失效
Source: NVD (National Vulnerability Database)
Vulnerability Title
Cisco IOS XE Software 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Cisco IOS XE Software是美国思科（Cisco）公司的一个操作系统。用于企业有线和无线访问，汇聚，核心和WAN的单一操作系统，Cisco IOS XE降低了业务和网络的复杂性。 Cisco IOS XE Software 存在安全漏洞，该漏洞源于遍历ALG的流量的数据验证不足造成的。攻击者可利用该漏洞向目标设备发送精心设计的流量来绕过ALG并打开不允许连接到位于ALG后面的远程设备的连接。
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 IOS XE Software | n/a | - |
II. Public POCs for CVE-2021-1616
| # | POC Description | Source Link | Shenlong Link |
|---|
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- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxe-h323alg-bypass-4vy2MP2Qvendor-advisoryx_refsource_CISCO
- https://nvd.nist.gov/vuln/detail/CVE-2021-1616
Same Patch Batch · Cisco · 2021-09-23 · 33 CVEs total
| CVE-2021-34770 | 10.0 CRITICAL | Cisco IOS XE Software for Catalyst 9000 Family Wireless Controllers CAPWAP Remote Code Exe |
| CVE-2021-34727 | 9.8 CRITICAL | Cisco IOS XE SD-WAN Software Buffer Overflow Vulnerability |
| CVE-2021-1619 | 9.8 CRITICAL | Cisco IOS XE Software NETCONF and RESTCONF Authentication Bypass Vulnerability |
| CVE-2021-1624 | 8.6 HIGH | Cisco IOS XE Software Rate Limiting Network Address Translation Denial of Service Vulnerab |
| CVE-2021-1622 | 8.6 HIGH | Cisco IOS XE Software for Cisco cBR-8 Converged Broadband Routers Common Open Policy Servi |
| CVE-2021-34768 | 8.6 HIGH | Cisco IOS XE Software for Catalyst 9000 Family Wireless Controllers CAPWAP Denial of Servi |
| CVE-2021-34769 | 8.6 HIGH | Cisco IOS XE Software for Catalyst 9000 Family Wireless Controllers CAPWAP Denial of Servi |
| CVE-2021-1615 | 8.6 HIGH | Cisco Embedded Wireless Controller Software for Catalyst Access Points Denial of Service V |
| CVE-2021-1611 | 8.6 HIGH | Cisco IOS XE Software for Catalyst 9800 Series Wireless Controllers EoGRE Denial of Servic |
| CVE-2021-1565 | 8.6 HIGH | Cisco IOS XE Software for Catalyst 9000 Family Wireless Controllers CAPWAP Denial of Servi |
| CVE-2021-1419 | 7.8 HIGH | Cisco Access Points SSH Management Privilege Escalation Vulnerability |
| CVE-2021-1623 | 7.7 HIGH | Cisco IOS XE Software for Cisco cBR-8 Converged Broadband Routers Simple Network Managemen |
| CVE-2021-34699 | 7.7 HIGH | Cisco IOS and IOS XE Software TrustSec CLI Parser Denial of Service Vulnerability |
| CVE-2021-1620 | 7.7 HIGH | Cisco IOS and IOS XE Software IKEv2 AutoReconnect Feature Denial of Service Vulnerability |
| CVE-2021-34767 | 7.4 HIGH | Cisco IOS XE Software for Catalyst 9800 Series Wireless Controllers IPv6 Denial of Service |
| CVE-2021-1621 | 7.4 HIGH | Cisco IOS XE Software Interface Queue Wedge Denial of Service Vulnerability |
| CVE-2021-34740 | 7.4 HIGH | Cisco Aironet Access Points WLAN Control Protocol Packet Buffer Leak Denial of Service Vul |
| CVE-2021-34714 | 7.4 HIGH | Multiple Cisco Operating Systems Unidirectional Link Detection Denial of Service Vulnerabi |
| CVE-2021-34703 | 6.8 MEDIUM | Cisco IOS and IOS XE Software Link Layer Discovery Protocol Denial of Service Vulnerabilit |
| CVE-2021-34729 | 6.7 MEDIUM | Cisco IOS XE SD-WAN Software Command Injection Vulnerability |
Showing top 20 of 33 CVEs. View all on vendor page → →
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V. Comments for CVE-2021-1616
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