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TI-2018-00380 Aliases CVE-2018-0421GHSA-3vp8-x92w-r8qp

Cisco Prime Access Registrar Denial of Service Vulnerability

Priority MEDIUM 49CWE-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 3.0 · NVD. Fix status from CNA. Impact type from CWE-399 and the CVSS impact.

Summary

A vulnerability in TCP connection management in Cisco Prime Access Registrar could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition when the application unexpectedly restarts. The vulnerability is due to incorrect handling of incoming TCP SYN packets to specific listening ports. The improper handling of the TCP SYN packets could cause a system file description to be allocated and not freed. An attacker could exploit this vulnerability by sending a crafted stream of TCP SYN packets to the application. A successful exploit could allow the attacker to cause the application to eventually restart if a file description cannot be obtained.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0348 89th 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 Prime Access Registrarall versions—No fix listedCNA
  • Cisco Prime Access Registrar VendorCisco Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:cisco:prime_access_registrar:*:*:*:*:*:*:*:*7.3 to before 7.3.0.4; 8.0 to before 8.0.1.1VulnerableCisco
cpe:2.3:a:cisco:prime_access_registrar_jumpstart:*:*:*:*:*:*:*:*7.3 to before 7.3.0.4; 8.0 to before 8.0.1.1VulnerableCisco
  • cpe:2.3:a:cisco:prime_access_registrar:*:*:*:*:*:*:*:* Versions 7.3 to before 7.3.0.4; 8.0 to before 8.0.1.1 Vulnerable ·Cisco
  • cpe:2.3:a:cisco:prime_access_registrar_jumpstart:*:*:*:*:*:*:*:* Versions 7.3 to before 7.3.0.4; 8.0 to before 8.0.1.1 Vulnerable ·Cisco

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2018-0421
  2. 2026-10-03 Alias added: GHSA-3vp8-x92w-r8qp

References

Advisory 1

  • TI-2023-23979 The HTTP/2 protocol allows a denial of service (server resource consumption) because… KEVCVSS 3.1HIGH 7.5
  • TI-2022-05185 Cisco Prime Access Registrar Appliance Cross-Site Scripting Vulnerability CVSS 3.1MEDIUM 5.5
  • TI-2021-13730 Cisco Prime Access Registrar Stored Cross-Site Scripting Vulnerability CVSS 3.1MEDIUM 4.8

Sources

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