CVE-2021-3956
mediumpriority · track · 21OT risk · elevatedEPSS 0.008 · 56 %ileEUUSEPSS · scored 2026-10-28
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
weaknesses
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affected products (6)
Products and version ranges known to be affected.
also known as (3)
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sources
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references (5)
External citations — patches, advisories, analysis.
- https://cxsecurity.com/cveshow/CVE-2021-3956/cnnvd
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-3956Patchcnnvd
- https://support.lenovo.com/us/en/product_security/LEN-72074cnnvd
- https://support.lenovo.com/us/en/product_security/LEN-72074enisa_euvd
- https://support.lenovo.com/us/en/product_security/LEN-72074Vendor Advisorynvd
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