CyberSecBulletin
CVE-2018-0161Exploited in the wildNVD status: Analyzed

Cisco IOS Software Resource Management Errors

CVE-2018-0161 is a medium-severity vulnerability in Cisco IOS, with a CVSS 3.1 base score of 6.3 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected Cisco IOS versions: Cisco IOS. The record does not name a fixed version, so check the vendor advisory. CISA added it to the Known Exploited Vulnerabilities catalogue on March 3, 2022, which means attacks have been observed in the wild.

Patch now

Attackers are already exploiting this vulnerability, according to CISA.

What to do

  1. Check which version of Cisco IOS you run against the affected versions below, and install the vendor's latest release.
  2. CISA's required action: Apply updates per vendor instructions.
  3. Read the advisory on tools.cisco.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
Cisco IOSCisco IOSCisco IOSNot stated
CiscoiOS15.2\(5\)eNot stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
HighSuccess depends on conditions outside the attacker's control.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
Confidentiality
NoneNo data is disclosed.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:N/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.16.3MediumNVD
CVSS 3.16.3MediumCISA (ADP)
CVSS 2.06.3MediumNVD

Official description

A vulnerability in the Simple Network Management Protocol (SNMP) subsystem of Cisco IOS Software running on certain models of Cisco Catalyst Switches could allow an authenticated, remote attacker to cause a denial of service (DoS) condition, aka a GET MIB Object ID Denial of Service Vulnerability. The vulnerability is due to a condition that could occur when the affected software processes an SNMP read request that contains a request for the ciscoFlashMIB object ID (OID). An attacker could trigger this vulnerability by issuing an SNMP GET request for the ciscoFlashMIB OID on an affected device. A successful exploit could cause the affected device to restart due to a SYS-3-CPUHOG. This vulnerability affects the following Cisco devices if they are running a vulnerable release of Cisco IOS Software and are configured to use SNMP Version 2 (SNMPv2) or SNMP Version 3 (SNMPv3): Cisco Catalyst 2960-L Series Switches, Cisco Catalyst Digital Building Series Switches 8P, Cisco Catalyst Digital Building Series Switches 8U. Cisco Bug IDs: CSCvd89541.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

Timeline

  1. CVE record published.
  2. Added to CISA's Known Exploited Vulnerabilities catalogue.
  3. Deadline for US federal agencies to remediate, set by CISA.
  4. CISA published its SSVC assessment (exploitation: active, automatable: no, technical impact: partial).
  5. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in Cisco IOS

All Cisco IOS vulnerabilities

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