CVE-2021-3956

Read-only configuration disclosure via unauthenticated LDAP bind

Published May 18, 2022 · Updated Aug 3, 2024

Authentication bypass in Lenovo XClarity Controller Third Quarter 2021 firmware allows remote attackers to view device configuration. The LDAP Authentication Only path permits access when the configured directory accepts an unauthenticated bind, without obtaining authenticated LDAP identity. Exploitation requires that mode and an LDAP server with unauthenticated-bind support; access is read-only and cannot change configuration.

CVSS severity4.3
Medium
EPSS probability0.77%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authentication bypass in Lenovo XClarity Controller Third Quarter 2021 firmware allows remote attackers to view device configuration. The LDAP Authentication Only path permits access when the configured directory accepts an unauthenticated bind, without obtaining authenticated LDAP identity. Exploitation requires that mode and an LDAP server with unauthenticated-bind support; access is read-only and cannot change configuration.

The record

CVE
CVE-2021-3956
Published
May 18, 2022
Updated
Aug 3, 2024
Vendor
Lenovo
Product
Lenovo XClarity Controller
Classifications
CWE-863
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 18, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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=various Third Quarter 2021 releases

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

Lenovo · Lenovo XClarity Controllerversion=various Third Quarter 2021 releases

Published CVSS scores

4.3Lenovo Group Ltd.CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
4.3NIST NVDAV:N/AC:M/Au:N/C:P/I:N/A:N
5.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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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)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-863Incorrect Authorization

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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