What’s Vulnerable › Vulnerabilities

CVE-2021-45100

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.9% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-12-16 · updated 2026-06-17
• Weakness: CWE-319

Description

The ksmbd server through 3.4.2, as used in the Linux kernel through 5.15.8, sometimes communicates in cleartext even though encryption has been enabled. This occurs because it sets the SMB2_GLOBAL_CAP_ENCRYPTION flag when using the SMB 3.1.1 protocol, which is a violation of the SMB protocol specification. When Windows 10 detects this protocol violation, it disables encryption.

Affected products

• Ksmbd Project Ksmbd: through 3.4.2
• NetApp H300E Firmware: all versions
• NetApp H300S Firmware: all versions
• NetApp H410C Firmware: all versions
• NetApp H410S Firmware: all versions
• NetApp H500E Firmware: all versions
• NetApp H500S Firmware: all versions
• NetApp H700E Firmware: all versions
• NetApp H700S Firmware: all versions

References

• https://github.com/cifsd-team/ksmbd/issues/550
• https://github.com/cifsd-team/ksmbd/pull/551
• https://marc.info/?l=linux-kernel&m=163961726017023&w=2
• https://security.netapp.com/advisory/ntap-20220107-0001/
• https://github.com/cifsd-team/ksmbd/issues/550
• https://github.com/cifsd-team/ksmbd/pull/551
• https://marc.info/?l=linux-kernel&m=163961726017023&w=2
• https://security.netapp.com/advisory/ntap-20220107-0001/

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