Is CVE-2021-3956 in the CISA KEV catalog?

No. CVE-2021-3956 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2021-3956?

CVE-2021-3956 has a CVSS v3 base score of 4.3 (MEDIUM).

What is the EPSS score for CVE-2021-3956?

CVE-2021-3956 has an EPSS score of 0.72% (49th percentile), estimating the probability of exploitation in the next 30 days.

How do I fix CVE-2021-3956?

Upgrade xclarity controller to 1.51_tgbt24l or later.

CVE & CISA-KEV Catalog

CVE-2021-3956

MEDIUM

4.3

CVSS v3

NVD

Description

A read-only authentication bypass vulnerability was reported in the Third Quarter 2021 release of Lenovo XClarity Controller (XCC) firmware affecting XCC devices configured in LDAP Authentication Only Mode and using an LDAP server that supports “unauthenticated bind”, such as Microsoft Active Directory. An unauthenticated user can gain read-only access to XCC in such a configuration, thereby allowing the XCC device configuration to be viewed but not changed. XCC devices configured to use local authentication, LDAP Authentication + Authorization Mode, or LDAP servers that support only “authenticated bind” and/or “anonymous bind” are not affected.

CWE-863Incorrect Authorization

How to fix

Remediation Available

xclarity controllerNVD

Affected:< 1.51_tgbt24lFixed in:1.51_tgbt24lCVE-2021-3956derived from NVD

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorAdjacent

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityLow

IntegrityNone

AvailabilityNone

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Exploit Intelligence

0.72%probability of exploitation in 30 days

49thpercentile

Moderate risk: more likely to be exploited than 49% of all known CVEs.

References

Vendor Advisory1

support.lenovo.com

Related Vulnerabilities

Other CWE-863 (Incorrect Authorization) vulnerabilities, ordered by exploit likelihood. View all

CVE	Severity	CVSS	EPSS	Exploited	Fix
CVE-2023-22518	Critical	9.8	100%	KEV + Ransom	Fix
CVE-2023-38035	Critical	9.8	100%	KEV + Ransom	-
CVE-2022-46169	Critical	9.8	100%	KEV	Fix
CVE-2025-29927	Critical	9.1	100%	-	Fix
CVE-2024-38856	Critical	9.8	99%	KEV	Fix
CVE-2020-36289	Medium	5.3	99%	-	Fix

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2024-11-21.