Amazon Linux 2 : samba (ALAS-2021-1680)

medium Nessus Plugin ID 151266

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New! Plugin Severity Now Using CVSS v3

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Synopsis

The remote Amazon Linux 2 host is missing a security update.

Description

The version of samba installed on the remote host is prior to 4.10.16-15. It is, therefore, affected by a vulnerability as referenced in the ALAS2-2021-1680 advisory.

- 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.
(CVE-2021-20254)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Run 'yum update samba' to update your system.

See Also

https://alas.aws.amazon.com/AL2/ALAS-2021-1680.html

https://access.redhat.com/security/cve/CVE-2021-20254

Plugin Details

Severity: Medium

ID: 151266

File Name: al2_ALAS-2021-1680.nasl

Version: 1.2

Type: local

Agent: unix

Published: 7/1/2021

Updated: 7/1/2021

Dependencies: ssh_get_info.nasl

Risk Information

CVSS Score Source: CVE-2021-20254

VPR

Risk Factor: Medium

Score: 6

CVSS v2

Risk Factor: Medium

Base Score: 4.9

Temporal Score: 3.6

Vector: AV:N/AC:M/Au:S/C:P/I:P/A:N

Temporal Vector: E:U/RL:OF/RC:C

CVSS v3

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5.9

Vector: CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:amazon:linux:ctdb, p-cpe:/a:amazon:linux:ctdb-tests, p-cpe:/a:amazon:linux:libsmbclient, p-cpe:/a:amazon:linux:libsmbclient-devel, p-cpe:/a:amazon:linux:libwbclient, p-cpe:/a:amazon:linux:libwbclient-devel, p-cpe:/a:amazon:linux:samba, p-cpe:/a:amazon:linux:samba-client, p-cpe:/a:amazon:linux:samba-client-libs, p-cpe:/a:amazon:linux:samba-common, p-cpe:/a:amazon:linux:samba-common-libs, p-cpe:/a:amazon:linux:samba-common-tools, p-cpe:/a:amazon:linux:samba-dc, p-cpe:/a:amazon:linux:samba-dc-libs, p-cpe:/a:amazon:linux:samba-debuginfo, p-cpe:/a:amazon:linux:samba-devel, p-cpe:/a:amazon:linux:samba-krb5-printing, p-cpe:/a:amazon:linux:samba-libs, p-cpe:/a:amazon:linux:samba-pidl, p-cpe:/a:amazon:linux:samba-python, p-cpe:/a:amazon:linux:samba-python-test, p-cpe:/a:amazon:linux:samba-test, p-cpe:/a:amazon:linux:samba-test-libs, p-cpe:/a:amazon:linux:samba-vfs-glusterfs, p-cpe:/a:amazon:linux:samba-winbind, p-cpe:/a:amazon:linux:samba-winbind-clients, p-cpe:/a:amazon:linux:samba-winbind-krb5-locator, p-cpe:/a:amazon:linux:samba-winbind-modules, cpe:/o:amazon:linux:2

Required KB Items: Host/local_checks_enabled, Host/AmazonLinux/release, Host/AmazonLinux/rpm-list

Exploit Ease: No known exploits are available

Patch Publication Date: 7/1/2021

Vulnerability Publication Date: 4/29/2021

Reference Information

CVE: CVE-2021-20254

IAVA: 2021-A-0208

ALAS: 2021-1680