CVE-2021-45100

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.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.15%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory marc.info Third-Party Advisory netapp.com
Affected: n/a n/a
Published at:
Updated at:

References

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

Frequently Asked Questions

What is the severity of CVE-2021-45100?
CVE-2021-45100 has been scored as a high severity vulnerability.
How to fix CVE-2021-45100?
To fix CVE-2021-45100, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-45100 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-45100 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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