CVE-2021-1406Network attack vector

Credential-hash disclosure via downloadable files

Published Apr 8, 2021 · Updated Nov 8, 2024

Information disclosure in Cisco Unified Communications Manager allows remote authenticated users to obtain system-user password hashes. The downloadable-file generation path includes sensitive system-user credential hashes in files made available to an authenticated requester. Exploitation requires valid elevated user credentials and a specific command sequence; the reported consequence is credential-hash exposure only.

CVSS severity4.9
Medium
EPSS probability1.08%
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 Unified Communications Manager allows remote authenticated users to obtain system-user password hashes. The downloadable-file generation path includes sensitive system-user credential hashes in files made available to an authenticated requester. Exploitation requires valid elevated user credentials and a specific command sequence; the reported consequence is credential-hash exposure only.

The record

CVE
CVE-2021-1406
Published
Apr 8, 2021
Updated
Nov 8, 2024
Vendor
ClamAV
Product
Cisco Unified Communications Manager
Classifications
CWE-200, CWE-538, T1003
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Apr 8, 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?

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  1. Affected versionversion=n/a

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

ClamAV · Cisco Unified Communications Managerversion=n/a

Published CVSS scores

4.9Cisco Systems, Inc.CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N/E:X/RL:X/RC:X
4.0NISTAV:N/AC:L/Au:S/C:P/I:N/A:N

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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-200Exposure of Sensitive Information to an Unauthorized Actor
CWE-538Insertion of Sensitive Information into Externally-Accessible File or Directory
T1003OS Credential Dumping

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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