CVE-2021-1600

Adjacent access to internal services via unrestricted forwarding

Published Jul 22, 2021 · Updated Nov 7, 2024

Improper access control in Cisco Intersight Virtual Appliance before 1.0.9-292 allows attackers on an adjacent network to reach internal services. The external management interface forwards crafted IPv4 or IPv6 traffic without sufficient restrictions, exposing services meant to remain internal. No authentication is required, and successful exploitation permits configuration changes and can interrupt appliance availability.

CVSS severity8.3
High
EPSS probability0.40%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper access control in Cisco Intersight Virtual Appliance before 1.0.9-292 allows attackers on an adjacent network to reach internal services. The external management interface forwards crafted IPv4 or IPv6 traffic without sufficient restrictions, exposing services meant to remain internal. No authentication is required, and successful exploitation permits configuration changes and can interrupt appliance availability.

The record

CVE
CVE-2021-1600
Published
Jul 22, 2021
Updated
Nov 7, 2024
Vendor
ClamAV
Product
Cisco Intersight Virtual Appliance
Classifications
CWE-284
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 22, 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 vectoradjacent
Required privilegesunauthenticated

What is affected?

ClamAV · Cisco Intersight Virtual Applianceversion=n/a

Published CVSS scores

8.3CiscoCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H
5.8NIST NVDAV:A/AC:L/Au:N/C:P/I:P/A:P

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-284Improper Access Control

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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