Vulnerability report

Exploited in the wild Confirmed confidence In CISA KEV

CVE-2004-1464

IOS Denial of Service

Cisco / IOS

Watch CVE-2004-1464 Browse KEV feed
Severity
CVSS 5.9 · Medium
Confidence
Confirmed
Exploit status
Exploited in the wild
EPSS
4.8%
First observed
—
Last observed
—

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2004-1464 is an unauthenticated vulnerability affecting 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...

Is it exploited?

Yes. Previdian tracks this CVE as a known exploited vulnerability. Confidence is confirmed. Listed in CISA KEV.

Who is affected?

Cisco / IOS.

What should we do?

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.

Overview

IOS Denial of Service

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.

View vendor advisory (opens in new tab)
Published
13 Feb 2005
Exploitation Reported
19 May 2023
Attack vector
Remote
Complexity
High
Privileges
None
User interaction
None

Tags

nessus_scanner ios edge cisa

CVE References

  • CVE Record CVE.org · CVE Record https://www.cve.org/CVERecord?id=CVE-2004-1464
  • 20040827 Cisco Telnet Denial of Service Vulnerability cisco.com · Vendor Advisory http://www.cisco.com/warp/public/707/cisco-sa-20040827-telnet.shtml
  • VU#384230 kb.cert.org · Third-Party Advisory http://www.kb.cert.org/vuls/id/384230
  • 12395 secunia.com · Third-Party Advisory http://secunia.com/advisories/12395/
  • cisco-ios-telnet-dos(17131) exchange.xforce.ibmcloud.com · VDB Entry https://exchange.xforce.ibmcloud.com/vulnerabilities/17131
  • 1011079 securitytracker.com · VDB Entry http://securitytracker.com/id?1011079
  • 11060 securityfocus.com · VDB Entry http://www.securityfocus.com/bid/11060

Exploitation evidence

Why Previdian marks this CVE as exploited

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploited in the wild

CISA

Recorded 19 May 2023

A trusted third party reported exploitation.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the Previdian Pro API.

Learn about Pro API access
Source Added
CISA First 2023-05-19 00:00 UTC

Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets
User-Agents
Callback hosts
0
0
0

Request targets and User-Agents available in Pro. Callback host details available in Enterprise.

Virtual patch status

No Previdian virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

Scanner Artifacts

Scanner and exploit-framework references linked to this CVE.

Scanner Reference Detected
Nessus https://www.tenable.com/plugins/nessus/48977 02 Jun 2025

Risk and context

Severity, weaknesses, and research context

CVSS v3.1

5.9 Medium

Potential damage if exploited. Separate from whether attackers are using it.

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS

4.8%

Estimated chance of exploitation in the next 30 days. Previdian's warning comes from evidence, not this score.

Weaknesses

Uncontrolled Resource Consumption CWE-400

All CVSS Scores

CVSS v3.1 5.9 Medium

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS v2.0 5.0 Medium

AV:N/AC:L/Au:N/C:N/I:N/A:P

Timeline

From disclosure to observed exploitation

  1. 09:26 UTC

    Nessus plugin available

    Scanner coverage available

  2. 00:00 UTC

    Added to CISA KEV

    Listed in the CISA Known Exploited Vulnerabilities catalog

  3. 05:00 UTC

    CVE published

    Vulnerability disclosed publicly

  4. 00:00 UTC

    CVE ID reserved

    Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

Start 14-day Pro trial Read API docs
  • Evidence confidence and provenance
  • First-party sensor telemetry
  • PoC and scanner references
  • Affected versions and enrichment
  • Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2004-1464

Sample API response 
{
  "cve_id": "CVE-2004-1464",
  "confidence": "Confirmed",
  "cvss_score": 5.9,
  "cvss_estimated": false,
  "epss_score": 0.0484,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "attempts": 0, "sensors": 0 }
}