Cisco · IOS and IOS XE
A flaw in the Cisco Cluster Management Protocol processing code in Cisco IOS and IOS XE Software allows malformed CMP-specific Telnet options to be accepted and processed over any Telnet connection, not just internal cluster communication. An unauthenticated remote attacker who can open a Telnet session to an affected device configured to accept Telnet connections can send such malformed options to cause a device reload or execute arbitrary code with elevated privileges.
A vulnerability in the Cisco Cluster Management Protocol (CMP) processing code in Cisco IOS and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a reload of an affected device or remotely execute code with elevated privileges. The Cluster Management Protocol utilizes Telnet internally as a signaling and command protocol between cluster members. The vulnerability is due to the combination of two factors: (1) the failure to restrict the use of CMP-specific Telnet options only to internal, local communications between cluster members and instead accept and process such options over any Telnet connection to an affected device; and (2) the incorrect processing of malformed CMP-specific Telnet options. An attacker could exploit this vulnerability by sending malformed CMP-specific Telnet options while establishing a Telnet session with an affected Cisco device configured to accept Telnet connections. An exploit could allow an attacker to execute arbitrary code and obtain full control of the device or cause a reload of the affected device. This affects Catalyst switches, Embedded Service 2020 switches, Enhanced Layer 2 EtherSwitch Service Module, Enhanced Layer 2/3 EtherSwitch Service Module, Gigabit Ethernet Switch Module (CGESM) for HP, IE Industrial Ethernet switches, ME 4924-10GE switch, RF Gateway 10, and SM-X Layer 2/3 EtherSwitch Service Module. Cisco Bug IDs: CSCvd48893.
First seen exploited the day it was disclosed. Public exploit code (Metasploit) was available the same day.
CISA KEV listing is when exploitation was confirmed, not necessarily the first attack.
Arbitrary code execution on the device
could allow an attacker to execute arbitrary code and obtain full control of the device
Device reload causes application or system DoS
or cause a reload of the affected device
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Reports are matched by finding the exact id CVE-2017-3881 in their text; nobody has reviewed the match. One passage is shown per report, at most 320 characters, linked to the original.
GNU bash system, specific the SMTP (this was part of the Shellshock CVEs)SID: 31975 - 31978, 31985, 32038, 32039, 32041 - 32043, 32069, 32335, 32336CVE-2017-3881: RCE for Cisco switchesSID: 41909 - 41910CVE-2017-6736: Remote Code Exploit (RCE) for Cisco integrated Service Router 2811SID: 43424 -…
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Pulses are indicator collections that anyone can publish. A mention is not confirmation of exploitation.