CVE-2021-45100

unknown
Published — · Modified —
CVSS v3
CVSS v2
VIR risk

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.

Predictions

Exploit likelihood
20%
Patch ETA

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

vendor Authored 2026-05-27

Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2021-45100

OS impact

OSVersionStatusFixed in
debian debianbookwormfixed5.15.15-1
debian debianbullseyefixed0
debian debianforkyfixed5.15.15-1
debian debiansidfixed5.15.15-1
debian debiantrixiefixed5.15.15-1

References

Verify integrity in audit chain (admin only). AS-IS.