| Name | CVE-2021-3738 |
| Description | In DCE/RPC it is possible to share the handles (cookies for resource state) between multiple connections via a mechanism called 'association groups'. These handles can reference connections to our sam.ldb database. However while the database was correctly shared, the user credentials state was only pointed at, and when one connection within that association group ended, the database would be left pointing at an invalid 'struct session_info'. The most likely outcome here is a crash, but it is possible that the use-after-free could instead allow different user state to be pointed at and this might allow more privileged access. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
| References | DSA-5003-1 |
Vulnerable and fixed packages
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|
| samba (PTS) | jessie, jessie (lts) | 2:4.2.14+dfsg-0+deb8u16 | vulnerable |
| stretch (security) | 2:4.5.16+dfsg-1+deb9u4 | vulnerable |
| stretch (lts), stretch | 2:4.5.16+dfsg-1+deb9u5 | vulnerable |
| buster (security), buster, buster (lts) | 2:4.9.5+dfsg-5+deb10u5 | vulnerable |
| bullseye (security), bullseye | 2:4.13.13+dfsg-1~deb11u6 | fixed |
| bookworm (security), bookworm | 2:4.17.12+dfsg-0+deb12u1 | fixed |
| trixie | 2:4.21.2+dfsg-3 | fixed |
| sid | 2:4.21.2+dfsg-4 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|
| samba | source | bullseye | 2:4.13.13+dfsg-1~deb11u2 | | DSA-5003-1 | |
| samba | source | (unstable) | 2:4.13.14+dfsg-1 | | | |
Notes
[buster] - samba <ignored> (Domain controller functionality is EOLed, see DSA-5015-1)
https://bugzilla.samba.org/show_bug.cgi?id=14468
https://www.samba.org/samba/security/CVE-2021-3738.html
[stretch] - samba <ignored> (Minor issue; affects Samba as AD DC; EOLed)
[jessie] - samba <ignored> (Minor issue; affects Samba as AD DC; EOLed)