CVE-2021-1134Network attack vector

Sensitive data interception via incomplete certificate validation

Published Jun 29, 2021 · Updated Nov 7, 2024

Improper certificate validation in Cisco Catalyst Center before 2.2.2.1 allows remote attackers to intercept and alter ISE client data. The ISE integration accepts a crafted X.509 certificate without complete validation when establishing a pxGrid connection to an ISE server. Exploitation requires an on-path position and enabled pxGrid integration, which is disabled by default, and exposes client data to reading and modification.

CVSS severity7.4
High
EPSS probability0.77%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper certificate validation in Cisco Catalyst Center before 2.2.2.1 allows remote attackers to intercept and alter ISE client data. The ISE integration accepts a crafted X.509 certificate without complete validation when establishing a pxGrid connection to an ISE server. Exploitation requires an on-path position and enabled pxGrid integration, which is disabled by default, and exposes client data to reading and modification.

The record

CVE
CVE-2021-1134
Published
Jun 29, 2021
Updated
Nov 7, 2024
Vendor
ClamAV
Product
Cisco Catalyst Center
Classifications
CWE-295, T1557
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 29, 2021CVE publishedPublication date reported by the CVE source.
  2. Nov 7, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=n/a

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ClamAV · Cisco Catalyst Centerversion=n/a

Published CVSS scores

7.4NIST NVDCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
5.8NIST NVDAV:N/AC:M/Au:N/C:P/I:P/A:N
7.4Cisco Systems, Inc.CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N/E:X/RL:X/RC:X

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-295Improper Certificate Validation
T1557Adversary-in-the-Middle

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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