CVE-2021-20254
Published: 29 April 2021
A flaw was found in samba. The Samba smbd file server must map Windows group identities (SIDs) into unix group ids (gids). The code that performs this had a flaw that could allow it to read data beyond the end of the array in the case where a negative cache entry had been added to the mapping cache. This could cause the calling code to return those values into the process token that stores the group membership for a user. The highest threat from this vulnerability is to data confidentiality and integrity.
Notes
| Author | Note |
|---|---|
| mdeslaur | 3.6 and higher |
Priority
Status
| Package | Release | Status |
|---|---|---|
|
samba Launchpad, Ubuntu, Debian |
bionic |
Released
(2:4.7.6+dfsg~ubuntu-0ubuntu2.23)
|
| focal |
Released
(2:4.11.6+dfsg-0ubuntu1.8)
|
|
| groovy |
Released
(2:4.12.5+dfsg-3ubuntu4.3)
|
|
| hirsute |
Released
(2:4.13.3+dfsg-1ubuntu2.1)
|
|
| trusty |
Released
(2:4.3.11+dfsg-0ubuntu0.14.04.20+esm11)
Available with Ubuntu Pro or Ubuntu Pro (Infra-only) |
|
| upstream |
Released
(4.14.1,4.13.6,4.12.13)
|
|
| xenial |
Released
(2:4.3.11+dfsg-0ubuntu0.16.04.34)
|
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 6.8 |
| Attack vector | Network |
| Attack complexity | High |
| Privileges required | Low |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | High |
| Integrity impact | High |
| Availability impact | None |
| Vector | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N |