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Fencer Intel
high 7.4

CVE-2019-1594 json

Cisco NX-OS Software 802.1X Extensible Authentication Protocol over LAN Denial of Service Vulnerability

published 7y ago modified 4mo ago also EUVD-2019-10151

cvss
7.4
version 3.0, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.8%
EPSS 0.8% chance of exploitation in 30 days, percentile 57%
public exploits
0
none known

Summary

A vulnerability in the 802.1X implementation for Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to incomplete input validation of Extensible Authentication Protocol over LAN (EAPOL) frames. An attacker could exploit this vulnerability by sending a crafted EAPOL frame to an interface on the targeted device. A successful exploit could allow the attacker to cause the Layer 2 (L2) forwarding process to restart multiple times, leading to a system-level restart of the device and a DoS condition. Note: This vulnerability affects only NX-OS devices configured with 802.1X functionality. Cisco Nexus 1000V Switch for VMware vSphere devices are affected in versions prior to 5.2(1)SV3(1.4b). Nexus 3000 Series Switches are affected in versions prior to 7.0(3)I7(4). Nexus 3500 Platform Switches are affected in versions prior to 7.0(3)I7(4). Nexus 2000, 5500, 5600, and 6000 Series Switches are affected in versions prior to 7.3(5)N1(1) and 7.1(5)N1(1b). Nexus 7000 and 7700 Series Switches are affected in versions prior to 8.2(3). Nexus 9000 Series Fabric Switches in ACI Mode are affected in versions prior to 13.2(1l). Nexus 9000 Series Switches in Standalone NX-OS Mode are affected in versions prior to 7.0(3)I7(4).

Patch / fix

  • Cisco Nexus 1000V Switch for VMware vSphere 5.2(1)SV3(1.4b)
  • Cisco Nexus 3000 Series Switches 7.0(3)I7(4)
  • Cisco Nexus 3500 Platform Switches 7.0(3)I7(4)
  • Cisco Nexus 2000, 5500, 5600, and 6000 Series Switches 7.1(5)N1(1b), 7.3(5)N1(1)
  • Cisco Nexus 7000 and 7700 Series Switches 8.2(3)
  • Cisco Nexus 9000 Series Fabric Switches in ACI Mode 13.2(1l)
  • Cisco Nexus 9000 Series Switches in Standalone NX-OS Mode 7.0(3)I7(4)

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CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
last yr.

Exploit prediction

0.81% chance of exploitation in the next 30 days, higher than 57% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.0 7.4 CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
NVD 3.0 7.4 CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
NVD 2.0 6.1 AV:A/AC:L/Au:N/C:N/I:N/A:C

Affected products

  • Cisco Nexus 1000V Switch for VMware vSphere
  • Cisco Nexus 3000 Series Switches
  • Cisco Nexus 3500 Platform Switches
  • Cisco Nexus 2000, 5500, 5600, and 6000 Series Switches
  • Cisco Nexus 7000 and 7700 Series Switches
  • Cisco Nexus 9000 Series Fabric Switches in ACI Mode
  • Cisco Nexus 9000 Series Switches in Standalone NX-OS Mode

Classification

Weakness
  • CWE-264 Permissions, Privileges, and Access Controls
  • CWE-20 Improper Input Validation

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.