CVE-2017-6740
CVE-2017-6740
In short
A flaw in Cisco IOS SNMP service allows attackers who know the read-only password (or have user credentials in SNMP v3) to send specially crafted packets that overflow a buffer, potentially executing malicious code or crashing the device.
Technical detail
Buffer overflow vulnerability in SNMP subsystem (CVE-2017-6740, CWE-119) affecting Cisco IOS/IOS XE across SNMP versions 1, 2c, and 3. Attack requires knowledge of SNMP community string (v2c/v1) or valid credentials (v3), with crafted packets triggering code execution or denial of service. Impact: arbitrary code execution and full system compromise.
Summary generated and translated by AI from the official description.
The Simple Network Management Protocol (SNMP) subsystem of Cisco IOS and IOS XE Software contains multiple vulnerabilities that could allow an authenticated, remote attacker to remotely execute code on an affected system or cause an affected system to reload. An attacker could exploit these vulnerabilities by sending a crafted SNMP packet to an affected system via IPv4 or IPv6. Only traffic directed to an affected system can be used to exploit these vulnerabilities.
The vulnerabilities are due to a buffer overflow condition in the SNMP subsystem of the affected software. The vulnerabilities affect all versions of SNMP - Versions 1, 2c, and 3. To exploit these vulnerabilities via SNMP Version 2c or earlier, the attacker must know the SNMP read-only community string for the affected system. To exploit these vulnerabilities via SNMP Version 3, the attacker must have user credentials for the affected system. A successful exploit could allow the attacker to execute arbitrary code and obtain full control of the affected system or cause the affected system to reload.
Customers are advised to apply the workaround as contained in the Workarounds section below. Fixed software information is available via the Cisco IOS Software Checker. All devices that have enabled SNMP and have not explicitly excluded the affected MIBs or OIDs should be considered vulnerable.
There are workarounds that address these vulnerabilities.
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
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https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170629-snmphttps://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170629-snmphttps://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2017-6740http://www.securityfocus.com/bid/99345http://www.securitytracker.com/id/1038808