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CVE-2017-12232

Cisco IOS Software for Cisco Integrated Services Routers Denial-of-Service Vulnerability

KEVMEDIUM 6.5EPSS 2.15%

Does this matter?

Known to be exploited in the wild (CISA KEV, CISA remediation deadline 24 March 2022). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.

Description

A vulnerability in the implementation of a protocol in Cisco Integrated Services Routers Generation 2 (ISR G2) Routers running Cisco IOS 15.0 through 15.6 could allow an unauthenticated, adjacent attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. The vulnerability is due to a misclassification of Ethernet frames. An attacker could exploit this vulnerability by sending a crafted Ethernet frame to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. Cisco Bug IDs: CSCvc03809.

CVSS 3.1
6.5 MEDIUMCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
2.15% probability · 82th percentile
Public exploits
None in Exploit-DB
CISA KEV
Listed 3 March 2022 · due 24 March 2022
Weakness
CWE-399
Affected
cisco/ios
Source
psirt@cisco.com
EPSS trend
0%3%5%27 October 2026: 2.15%27 October 202627 October 2026

EPSS 2.2% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

CISA notes

Apply updates per vendor instructions. https://nvd.nist.gov/vuln/detail/CVE-2017-12232

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.