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Fencer Intel
high 7.4

CVE-2021-1134 json

Cisco DNA Center Certificate Validation Vulnerability

published 5y ago modified 4mo ago also EUVD-2021-6601

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 55%
public exploits
0
none known

Summary

A vulnerability in the Cisco Identity Services Engine (ISE) integration feature of the Cisco DNA Center Software could allow an unauthenticated, remote attacker to gain unauthorized access to sensitive data. The vulnerability is due to an incomplete validation of the X.509 certificate used when establishing a connection between DNA Center and an ISE server. An attacker could exploit this vulnerability by supplying a crafted certificate and could then intercept communications between the ISE and DNA Center. A successful exploit could allow the attacker to view and alter sensitive information that the ISE maintains about clients that are connected to the network.

Patch / fix

  • cisco catalyst_center 2.2.2.1

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CISA SSVC

Exploitation
none
Automatable
no
Technical impact
total
Assessed
2y ago

Exploit prediction

0.77% chance of exploitation in the next 30 days, higher than 55% 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:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
NVD 3.1 7.4 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
NVD 2.0 5.8 AV:N/AC:M/Au:N/C:P/I:P/A:N

Affected products

  • Cisco Cisco Digital Network Architecture Center (DNA Center)

Classification

Weakness
  • CWE-295 Improper Certificate 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.