CVE-2021-1381

Debug console access via insufficient command authorization

Published Mar 24, 2021 · Updated Nov 8, 2024

Improper authorization in Cisco IOS XE Software allows physically proximate attackers to open a debugging console through hardware commands. The hardware-platform command path fails to enforce command-authorization restrictions before enabling the otherwise protected debugging console. Exploitation requires either unauthenticated physical access to an IR1101 or ESR6300 device, or local high-privilege access, and grants console capabilities affecting device confidentiality and integrity.

CVSS severity6.1
Medium
EPSS probability0.27%
Next 30 days · Sep 17, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authorization in Cisco IOS XE Software allows physically proximate attackers to open a debugging console through hardware commands. The hardware-platform command path fails to enforce command-authorization restrictions before enabling the otherwise protected debugging console. Exploitation requires either unauthenticated physical access to an IR1101 or ESR6300 device, or local high-privilege access, and grants console capabilities affecting device confidentiality and integrity.

The record

CVE
CVE-2021-1381
Published
Mar 24, 2021
Updated
Nov 8, 2024
Vendor
ClamAV
Product
Cisco IOS XE Software
Classifications
CWE-489, CAPEC-661, CAPEC-121, T1059.008
Attack vector
physical
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 24, 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 vectorphysical
Required privilegesunauthenticated

What is affected?

ClamAV · Cisco IOS XE Softwareversion=n/a

Published CVSS scores

3.6NIST National Vulnerability DatabaseAV:L/AC:L/Au:N/C:P/I:P/A:N
6.1Cisco Systems, Inc.CVSS:3.1/AV:P/AC:L/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)
Vectorphysical
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-489Active Debug Code
CAPEC-661Root/Jailbreak Detection Evasion via Debugging
CAPEC-121Exploit Non-Production Interfaces
T1059.008Command and Scripting Interpreter Network Device CLI

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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