CVEs / CVE-2017-12240
CVE-2017-12240: Cisco IOS and IOS XE Software DHCP Remote Code Execution Vulnerability
- Known exploited in the CISA KEV catalog since 3 Mar 2022
- critical 9.8 CVSS 3.1 (NVD)
- EPSS 13.7% chance of exploitation in the next 30 days, higher than 96% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
The Dynamic Host Configuration Protocol (DHCP) relay subsystem of Cisco IOS 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.
Description
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.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| n/a Cisco IOS and IOS XE | Cisco IOS and IOS XE | — |
Exploitation
| In CISA KEV since | 3 Mar 2022 |
|---|---|
| Due date for US federal agencies | 24 Mar 2022 |
| Used in ransomware campaigns | Unknown |
| Required action | Apply updates per vendor instructions. |
Severity
| CVSS 3.1 | 9.8 criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HScored by NVD |
|---|---|
| Weakness | CWE-20, CWE-119 |
References
- CVE-2017-12240 on NVD
- CVE-2017-12240 in the CISA KEV catalog
- 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
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.