CVE-2021-1535Network attack vector

Sensitive information disclosure via unauthenticated cluster requests

Published May 6, 2021 · Updated Nov 8, 2024

Information disclosure in Cisco Catalyst SD-WAN Manager before 20.5.1 allows remote attackers to read sensitive data via cluster-interface requests. The cluster management interface returns sensitive information for a crafted request without authenticating the requester. Exposure requires cluster mode and network access to the cluster interface, which Cisco states should not be externally accessible.

CVSS severity5.3
Medium
EPSS probability1.22%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in Cisco Catalyst SD-WAN Manager before 20.5.1 allows remote attackers to read sensitive data via cluster-interface requests. The cluster management interface returns sensitive information for a crafted request without authenticating the requester. Exposure requires cluster mode and network access to the cluster interface, which Cisco states should not be externally accessible.

The record

CVE
CVE-2021-1535
Published
May 6, 2021
Updated
Nov 8, 2024
Vendor
ClamAV
Product
Cisco Catalyst SD-WAN Manager
Classifications
CWE-497
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 6, 2021CVE publishedPublication date reported by the CVE source.
  2. Nov 8, 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 SD-WAN Managerversion=n/a

Published CVSS scores

5.3Cisco Systems, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/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.

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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-497Exposure of Sensitive System Information to an Unauthorized Control Sphere

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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