Known exploited vulnerability
CVE-2017-3881
The short answer
CVE-2017-3881 affects n/a Cisco IOS and IOS XE Software and is rated critical (CVSS 9.8). CISA added it to the Known Exploited Vulnerabilities catalog on 2022-03-25: attackers are using it, so patch it first.
What it is
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.
Weakness: CWE-20.
Severity
9.8 critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Exploited (CISA KEV)
Yes, since Mar 25, 2022
Federal due date Apr 15, 2022
EPSS, next 30 days
99%
Higher than 100% of scored CVEs
How it can be exploited
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
What CISA says to do
Apply updates per vendor instructions.
Affected products
Cisco IOS and IOS XE Software. NVD's record lists the exact affected versions.
References
- tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170317-cmp Vendor Advisory
- www.exploit-db.com/exploits/41872/ ExploitThird Party AdvisoryVDB Entry
- www.exploit-db.com/exploits/41874/ Broken Link
- tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170317-cmp Vendor Advisory
- www.exploit-db.com/exploits/41872/ ExploitThird Party AdvisoryVDB Entry
- www.exploit-db.com/exploits/41874/ Broken Link
- www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2017-3881 US Government Resource
Questions
Is CVE-2017-3881 being exploited?
Yes. CISA added CVE-2017-3881 to its Known Exploited Vulnerabilities catalog on 2022-03-25, with a federal remediation due date of 2022-04-15.
How do I fix CVE-2017-3881?
CISA's required action: Apply updates per vendor instructions.
From NVD, CISA KEV, FIRST EPSS and OSV.dev, checked . Status on NVD: Analyzed. The description is NVD's text, quoted as published.
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