CVE-2021-1578Network attack vector

Administrator credential disclosure via fail-open API policy

Published Aug 25, 2021 · Updated Nov 7, 2024

Privilege escalation in Cisco APIC 5.0 and 5.1 before 5.1(3e) allows remote authenticated users to obtain Administrator credentials. The affected API endpoint fails open because an improper policy default permits a request made with a nonprivileged ACI MSO credential to return Administrator credentials. Exploitation requires the APIC to be managed by ACI MSO 3.0(2d) through 3.1(1i) installed on a Cisco Application Services Engine.

CVSS severity8.8
High
EPSS probability1.97%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Privilege escalation in Cisco APIC 5.0 and 5.1 before 5.1(3e) allows remote authenticated users to obtain Administrator credentials. The affected API endpoint fails open because an improper policy default permits a request made with a nonprivileged ACI MSO credential to return Administrator credentials. Exploitation requires the APIC to be managed by ACI MSO 3.0(2d) through 3.1(1i) installed on a Cisco Application Services Engine.

The record

CVE
CVE-2021-1578
Published
Aug 25, 2021
Updated
Nov 7, 2024
Vendor
ClamAV
Product
Cisco Application Policy Infrastructure Controller (APIC)
Classifications
CWE-636, T1078
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 25, 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 privilegesauthenticated

What is affected?

ClamAV · Cisco Application Policy Infrastructure Controller (APIC)version=n/a

Published CVSS scores

9.0NIST NVDAV:N/AC:L/Au:S/C:C/I:C/A:C
8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
8.8CiscoCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-636Not Failing Securely ('Failing Open')
T1078Valid Accounts

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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