CVE-2021-1128

Configuration disclosure via incomplete CLI privilege enforcement

Published Feb 4, 2021 · Updated Nov 8, 2024

Information disclosure in the CLI parser of Cisco IOS XR Software allows local users to read restricted configuration data through a command. The parser insufficiently applies privilege restrictions while executing a specific command, exposing configuration data beyond the invoking user's authorization. An authenticated CLI session and low-privileged local access are required; Cisco has not publicly identified the affected command.

CVSS severity5.5
Medium
EPSS probability0.34%
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 the CLI parser of Cisco IOS XR Software allows local users to read restricted configuration data through a command. The parser insufficiently applies privilege restrictions while executing a specific command, exposing configuration data beyond the invoking user's authorization. An authenticated CLI session and low-privileged local access are required; Cisco has not publicly identified the affected command.

The record

CVE
CVE-2021-1128
Published
Feb 4, 2021
Updated
Nov 8, 2024
Vendor
ClamAV
Product
Cisco IOS XR Software
Classifications
CWE-201, T1005
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 4, 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 vectorlocal
Required privilegesauthenticated

What is affected?

ClamAV · Cisco IOS XR Softwareversion=n/a

Published CVSS scores

5.5CiscoCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N/E:X/RL:X/RC:X
2.1NIST NVDAV:L/AC:L/Au:N/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.

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)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-201Insertion of Sensitive Information Into Sent Data
T1005Data from Local System

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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