CVE-2004-1464
Cisco IOS Denial-of-Service Vulnerability
Cisco IOS
Cisco IOS 12.2(15) and earlier allows remote attackers to cause a denial of service (refused VTY (virtual terminal) connections), via a crafted TCP connection to the Telnet or reverse Telnet port.
Exploitation status
CISA Known Exploited Vulnerabilities
Listed by CISA on 19 May 2023. US federal agencies were required to remediate it by 9 June 2023.
EPSS — exploitation probability
FIRST puts the probability of exploitation activity in the next 30 days at 4.8%, which is higher than 92.1% of all scored vulnerabilities. EPSS is a forecast of activity, not a measure of severity, and it is rescored daily.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Frequently asked questions
Is CVE-2004-1464 being exploited by ransomware groups?
No ransomware group in this database is currently recorded as exploiting CVE-2004-1464.
What does CVE-2004-1464 affect?
CVE-2004-1464 affects Cisco IOS. Cisco IOS 12.2(15) and earlier allows remote attackers to cause a denial of service (refused VTY (virtual terminal) connections), via a crafted TCP connection to the Telnet or reverse Telnet port.
How severe is CVE-2004-1464?
CVE-2004-1464 is rated MEDIUM with a CVSS base score of 5.9. EPSS puts the probability of exploitation in the next 30 days at 4.8%, higher than 92.1% of all scored vulnerabilities. It is listed in the CISA Known Exploited Vulnerabilities catalog, with a federal remediation deadline of 9 June 2023.
How should organisations respond to CVE-2004-1464?
Apply the vendor patch for Cisco IOS as the first priority, and treat any internet-facing instance as the most urgent. Because this vulnerability is associated with ransomware activity, also review whether the affected systems were reachable before patching, rather than assuming that patching alone closes the incident.