AEGLIX vulnerability intelligence
CVE-2017-12240
CRITICAL · CVSS 9.8 · Analyzed
Published: 2017-09-29 · Updated: 2026-06-17 · Source: NVD
Vulnerability overview
The DHCP relay subsystem of Cisco IOS 12.2 through 15.6 and Cisco IOS XE Software contains a vulnerability that could allow an unauthenticated, remote attacker to execute arbitrary code and gain full control of an affected system. The attacker could also cause an affected system to reload, resulting in a denial of service (DoS) condition. The vulnerability is due to a buffer overflow condition in the DHCP relay subsystem of the affected software. An attacker could exploit this vulnerability by sending a crafted DHCP Version 4 (DHCPv4) packet to an affected system. A successful exploit could allow the attacker to execute arbitrary code and gain full control of the affected system or cause the affected system to reload, resulting in a DoS condition. Cisco Bug IDs: CSCsm45390, CSCuw77959.
Severity and scoring
- CVSS score
- 9.8 · CRITICAL
- CVSS version
- 3.1
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Weaknesses
- CWE-119, CWE-20
CVSS measures technical severity; it does not establish whether this vulnerability is being exploited in your environment.
Known exploitation and remediation
Listed in CISA’s Known Exploited Vulnerabilities catalog.
- Affected product
- Cisco · IOS and IOS XE Software
- Added to catalog
- 2022-03-03
- Required action
- Apply updates per vendor instructions.
- CISA remediation due date
- 2022-03-24
CISA deadlines apply to the organizations covered by its directives. Confirm your own remediation requirements.
Verify affected versions and patch availability in the vendor advisory before making changes.
Affected products and versions
cpe:2.3:o:cisco:ios:*:*:*:*:*:*:*:*
From (inclusive): 12.2
Through (inclusive): 15.6
These are NVD CPE applicability entries. Some products depend on configuration conditions; consult the official record to confirm applicability.
Advisories and references
- http://www.securityfocus.com/bid/101034
Broken Link · Third Party Advisory · VDB Entry
- http://www.securitytracker.com/id/1039445
Broken Link · Third Party Advisory · VDB Entry
- https://quickview.cloudapps.cisco.com/quickview/bug/CSCsm45390
Vendor Advisory
- https://quickview.cloudapps.cisco.com/quickview/bug/CSCuw77959
Vendor Advisory
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170927-dhcp
Vendor Advisory
- http://www.securityfocus.com/bid/101034
Broken Link · Third Party Advisory · VDB Entry
- http://www.securitytracker.com/id/1039445
Broken Link · Third Party Advisory · VDB Entry
- https://quickview.cloudapps.cisco.com/quickview/bug/CSCsm45390
Vendor Advisory
- https://quickview.cloudapps.cisco.com/quickview/bug/CSCuw77959
Vendor Advisory
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170927-dhcp
Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2017-12240
US Government Resource