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TI-2019-09448 Aliases CVE-2019-12652GHSA-qr97-v3cv-xgjc

Cisco Catalyst 4000 Series Switches TCP Denial of Service Vulnerability

Priority MEDIUM 44CWE-399Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-399 and the CVSS impact.

Summary

A vulnerability in the ingress packet processing function of Cisco IOS Software for Cisco Catalyst 4000 Series Switches could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to improper resource allocation when processing TCP packets directed to the device on specific Cisco Catalyst 4000 Series Switches. An attacker could exploit this vulnerability by sending crafted TCP streams to an affected device. A successful exploit could cause the affected device to run out of buffer resources, impairing operations of control plane and management plane protocols, resulting in a DoS condition. This vulnerability can be triggered only by traffic that is destined to an affected device and cannot be exploited using traffic that transits an affected device.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.02708 86th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
CiscoCisco IOS 15.0(1)XO1all versions—No fix listedCNA
  • Cisco IOS 15.0(1)XO1 VendorCisco Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 7

CPEVersionsRoleVendor
cpe:2.3:o:cisco:ios:15.2\(3\)e1:*:*:*:*:*:*:*15.2(3)e1VulnerableCisco
cpe:2.3:o:cisco:ios:15.2\(4\)e3:*:*:*:*:*:*:*15.2(4)e3VulnerableCisco
cpe:2.3:h:cisco:catalyst_4500_supervisor_engine_6-e:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:catalyst_4500_supervisor_engine_6l-e:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:catalyst_4900m:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:catalyst_4948e:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:catalyst_4948e-f:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
  • cpe:2.3:o:cisco:ios:15.2\(3\)e1:*:*:*:*:*:*:* Versions 15.2(3)e1 Vulnerable ·Cisco
  • cpe:2.3:o:cisco:ios:15.2\(4\)e3:*:*:*:*:*:*:* Versions 15.2(4)e3 Vulnerable ·Cisco
  • cpe:2.3:h:cisco:catalyst_4500_supervisor_engine_6-e:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:catalyst_4500_supervisor_engine_6l-e:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:catalyst_4900m:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:catalyst_4948e:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:catalyst_4948e-f:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2019-12652
  2. 2026-10-03 Alias added: GHSA-qr97-v3cv-xgjc

References

Advisory 1

  • TI-2018-00138 Improper input validation in Cisco IOS and IOS XE KEVCVSS 3.1CRITICAL 9.8
  • TI-2017-09019 Improper input validation in Cisco IOS and IOS XE KEVCVSS 3.1CRITICAL 9.8
  • TI-2017-02977 Improper input validation in Cisco IOS and IOS XE Software KEVCVSS 3.1CRITICAL 9.8
  • TI-2018-00135 Memory corruption in Cisco IOS, IOS XE, and IOS XR KEVCVSS 3.1HIGH 8.8
  • TI-2017-04499 Memory corruption in Cisco IOS KEVCVSS 3.1HIGH 8.8
  • TI-2017-04498 Memory corruption in Cisco IOS KEVCVSS 3.1HIGH 8.8
See all 617 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences