Vulnerability Name:

CVE-2021-1611 (CCN-209910)

Assigned:2020-11-13
Published:2021-09-21
Updated:2022-07-08
Summary:A vulnerability in Ethernet over GRE (EoGRE) packet processing of Cisco IOS XE Wireless Controller Software for the Cisco Catalyst 9800 Family Wireless Controller, Embedded Wireless Controller, and Embedded Wireless on Catalyst 9000 Series Switches could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper processing of malformed EoGRE packets. An attacker could exploit this vulnerability by sending malicious packets to the affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.
CVSS v3 Severity:8.6 High (CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H)
7.5 High (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope:Scope (S): Changed
Impact Metrics:Confidentiality (C): None
Integrity (I): None
Availibility (A): High
8.6 High (CCN CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H)
7.5 High (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope:Scope (S): Changed
Impact Metrics:Confidentiality (C): None
Integrity (I): None
Availibility (A): High
CVSS v2 Severity:5.0 Medium (CVSS v2 Vector: AV:N/AC:L/Au:N/C:N/I:N/A:P)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Low
Authentication (Au): None
Impact Metrics:Confidentiality (C): None
Integrity (I): None
Availibility (A): Partial
7.8 High (CCN CVSS v2 Vector: AV:N/AC:L/Au:N/C:N/I:N/A:C)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Low
Athentication (Au): None
Impact Metrics:Confidentiality (C): None
Integrity (I): None
Availibility (A): Complete
Vulnerability Type:CWE-noinfo
Vulnerability Consequences:Denial of Service
References:Source: MITRE
Type: CNA
CVE-2021-1611

Source: XF
Type: UNKNOWN
cisco-cve20211611-dos(209910)

Source: CCN
Type: Cisco Security Advisory cisco-sa-ewlc-gre-6u4ELzAT
Cisco IOS XE Software for Catalyst 9800 Series Wireless Controllers EoGRE Denial of Service Vulnerability

Source: CISCO
Type: Patch, Vendor Advisory
20210922 Cisco IOS XE Software for Catalyst 9800 Series Wireless Controllers EoGRE Denial of Service Vulnerability

Vulnerable Configuration:Configuration 1:
  • cpe:/o:cisco:ios_xe:*:*:*:*:*:*:*:* (Version < 17.3.1)
  • AND
  • cpe:/h:cisco:catalyst_9800-l:-:*:*:*:*:*:*:*
  • OR cpe:/h:cisco:catalyst_9800-l-c:-:*:*:*:*:*:*:*
  • OR cpe:/h:cisco:catalyst_9800-l-f:-:*:*:*:*:*:*:*
  • OR cpe:/h:cisco:catalyst_9800-40:-:*:*:*:*:*:*:*
  • OR cpe:/h:cisco:catalyst_9800-80:-:*:*:*:*:*:*:*
  • OR cpe:/h:cisco:catalyst_9800-cl:-:*:*:*:*:*:*:*
  • OR cpe:/h:cisco:catalyst_9800:-:*:*:*:*:*:*:*

    • Configuration CCN 1:
  • cpe:/o:cisco:ios_xe_software:*:*:*:*:*:*:*:*

    • * Denotes that component is vulnerable
    BACK
    cisco ios xe *
    cisco catalyst 9800-l -
    cisco catalyst 9800-l-c -
    cisco catalyst 9800-l-f -
    cisco catalyst 9800-40 -
    cisco catalyst 9800-80 -
    cisco catalyst 9800-cl -
    cisco catalyst 9800 -
    cisco ios xe software *