| Name | 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. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
Vulnerable and fixed packages
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|
| linux (PTS) | jessie, jessie (lts) | 3.16.84-1 | vulnerable |
| stretch (security) | 4.9.320-2 | fixed |
| stretch (lts), stretch | 4.9.320-3 | fixed |
| buster | 4.19.249-2 | fixed |
| buster (security) | 4.19.304-1 | fixed |
| bullseye | 5.10.209-2 | fixed |
| bullseye (security) | 5.10.205-2 | fixed |
| bookworm | 6.1.76-1 | fixed |
| bookworm (security) | 6.1.85-1 | fixed |
| trixie | 6.6.15-2 | fixed |
| sid | 6.7.9-2 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|
| linux | source | stretch | (not affected) | | | |
| linux | source | buster | (not affected) | | | |
| linux | source | bullseye | (not affected) | | | |
| linux | source | (unstable) | 5.15.15-1 | unimportant | | |
Notes
[bullseye] - linux <not-affected> (Vulnerable code not present)
[buster] - linux <not-affected> (Vulnerable code not present)
[stretch] - linux <not-affected> (Vulnerable code not present)
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
SMB_SERVER enabled only as module since 5.16~rc1-1~exp1.