Cisco · IOS and IOS XE Software
The Simple Network Management Protocol (SNMP) subsystem of Cisco IOS and IOS XE Software contains a buffer overflow flaw that affects SNMP Versions 1, 2c, and 3. An attacker with network access to an affected system, reachable over IPv4 or IPv6 via a crafted SNMP packet, could execute arbitrary code with full control of the device or cause it to reload, but must first hold valid credentials: the SNMP read-only community string for Versions 2c and earlier, or user credentials for Version 3.
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.
First seen exploited 21 months after disclosure. Public exploit code (Exploit-DB) appeared 6 months after disclosure.
CISA KEV listing is when exploitation was confirmed, not necessarily the first attack.
Requires valid SNMP community string or credentials
the attacker must know the SNMP read-only community string for the affected system
Buffer overflow yields arbitrary code execution
could allow the attacker to execute arbitrary code and obtain full control
Crafted packet causes device reload, denial of service
or cause the affected system to reload
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Reports are matched by finding the exact id CVE-2017-6736 in their text; nobody has reviewed the match. One passage is shown per report, at most 320 characters, linked to the original.
…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 - 43432CVE-2017-12617: RCE affecting Apache web servers running TomcatSID:
Pulses are indicator collections that anyone can publish. A mention is not confirmation of exploitation.