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.

Priority

Medium

Status

Package Release Status
samba
Launchpad, Ubuntu, Debian
Upstream
Released (4.14.1,4.13.6,4.12.13)
Ubuntu 21.04 (Hirsute Hippo)
Released (2:4.13.3+dfsg-1ubuntu2.1)
Ubuntu 20.10 (Groovy Gorilla)
Released (2:4.12.5+dfsg-3ubuntu4.3)
Ubuntu 20.04 LTS (Focal Fossa)
Released (2:4.11.6+dfsg-0ubuntu1.8)
Ubuntu 18.04 LTS (Bionic Beaver)
Released (2:4.7.6+dfsg~ubuntu-0ubuntu2.23)
Ubuntu 16.04 ESM (Xenial Xerus)
Released (2:4.3.11+dfsg-0ubuntu0.16.04.34)
Ubuntu 14.04 ESM (Trusty Tahr)
Released (2:4.3.11+dfsg-0ubuntu0.14.04.20+esm11)