Cisco IOS Denial-of-Service Vulnerability

Added to KEV
2023-05-19
Federal due date
2023-06-09
Vendor
Cisco
Product
IOS
EPSS
84.8th percentile (score 0.022, as of 2026-06-08)
NVD CVSS v3.1
Ransomware use
Unknown
Upstream
https://nvd.nist.gov/vuln/detail/CVE-2004-1464

CISA short description

Cisco IOS contains an unspecified vulnerability that may block further telnet, reverse telnet, Remote Shell (RSH), Secure Shell (SSH), and in some cases, Hypertext Transport Protocol (HTTP) access to the Cisco device.

Required action

Apply updates per vendor instructions.

EPSS percentile is the FIRST.org exploit-probability ranking as of the date noted above; it moves daily. CVSS reflects NVD's analysis at time of publication.