Amazon Linux 2023 : libnetapi, libnetapi-devel, libsmbclient (ALAS2023-2023-416)

critical Nessus Plugin ID 184412

Synopsis

The remote Amazon Linux 2023 host is missing a security update.

Description

It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2023-2023-416 advisory.

- A path traversal vulnerability was identified in Samba when processing client pipe names connecting to Unix domain sockets within a private directory. Samba typically uses this mechanism to connect SMB clients to remote procedure call (RPC) services like SAMR LSA or SPOOLSS, which Samba initiates on demand.
However, due to inadequate sanitization of incoming client pipe names, allowing a client to send a pipe name containing Unix directory traversal characters (../). This could result in SMB clients connecting as root to Unix domain sockets outside the private directory. If an attacker or client managed to send a pipe name resolving to an external service using an existing Unix domain socket, it could potentially lead to unauthorized access to the service and consequential adverse events, including compromise or service crashes. (CVE-2023-3961)

- A vulnerability was discovered in Samba, where the flaw allows SMB clients to truncate files, even with read-only permissions when the Samba VFS module acl_xattr is configured with acl_xattr:ignore system acls = yes. The SMB protocol allows opening files when the client requests read-only access but then implicitly truncates the opened file to 0 bytes if the client specifies a separate OVERWRITE create disposition request. The issue arises in configurations that bypass kernel file system permissions checks, relying solely on Samba's permissions. (CVE-2023-4091)

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

Solution

Run 'dnf update samba --releasever 2023.2.20231030' to update your system.

See Also

https://alas.aws.amazon.com/AL2023/ALAS-2023-416.html

https://alas.aws.amazon.com/cve/html/CVE-2023-3961.html

https://alas.aws.amazon.com/cve/html/CVE-2023-4091.html

https://alas.aws.amazon.com/faqs.html

Plugin Details

Severity: Critical

ID: 184412

File Name: al2023_ALAS2023-2023-416.nasl

Version: 1.2

Type: local

Agent: unix

Published: 11/4/2023

Updated: 11/14/2023

Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: Critical

Base Score: 10

Temporal Score: 7.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C

CVSS Score Source: CVE-2023-3961

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 8.8

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

Temporal Vector: CVSS:3.0/E:P/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:amazon:linux:libsmbclient, p-cpe:/a:amazon:linux:samba, p-cpe:/a:amazon:linux:samba-pidl, p-cpe:/a:amazon:linux:libsmbclient-debuginfo, p-cpe:/a:amazon:linux:libwbclient, p-cpe:/a:amazon:linux:samba-common-libs, p-cpe:/a:amazon:linux:samba-dcerpc, p-cpe:/a:amazon:linux:samba-libs, p-cpe:/a:amazon:linux:samba-test-libs-debuginfo, p-cpe:/a:amazon:linux:samba-usershares, p-cpe:/a:amazon:linux:samba-vfs-iouring, p-cpe:/a:amazon:linux:samba-winbind-krb5-locator, p-cpe:/a:amazon:linux:samba-common-tools-debuginfo, p-cpe:/a:amazon:linux:samba-debugsource, p-cpe:/a:amazon:linux:samba-test, p-cpe:/a:amazon:linux:samba-client-libs, p-cpe:/a:amazon:linux:samba-client-debuginfo, p-cpe:/a:amazon:linux:libnetapi-debuginfo, p-cpe:/a:amazon:linux:samba-winbind-krb5-locator-debuginfo, p-cpe:/a:amazon:linux:samba-test-libs, p-cpe:/a:amazon:linux:samba-winbind-debuginfo, p-cpe:/a:amazon:linux:libnetapi, p-cpe:/a:amazon:linux:libwbclient-debuginfo, p-cpe:/a:amazon:linux:samba-ldb-ldap-modules-debuginfo, p-cpe:/a:amazon:linux:libwbclient-devel, p-cpe:/a:amazon:linux:samba-winbind-clients, p-cpe:/a:amazon:linux:samba-common-libs-debuginfo, p-cpe:/a:amazon:linux:samba-ldb-ldap-modules, p-cpe:/a:amazon:linux:samba-client-libs-debuginfo, p-cpe:/a:amazon:linux:samba-winbind-clients-debuginfo, p-cpe:/a:amazon:linux:python3-samba-debuginfo, p-cpe:/a:amazon:linux:samba-tools, p-cpe:/a:amazon:linux:samba-krb5-printing, p-cpe:/a:amazon:linux:samba-libs-debuginfo, p-cpe:/a:amazon:linux:samba-dcerpc-debuginfo, p-cpe:/a:amazon:linux:samba-vfs-iouring-debuginfo, p-cpe:/a:amazon:linux:samba-winbind, p-cpe:/a:amazon:linux:samba-debuginfo, p-cpe:/a:amazon:linux:python3-samba, p-cpe:/a:amazon:linux:samba-winbind-modules-debuginfo, p-cpe:/a:amazon:linux:samba-dc-libs-debuginfo, cpe:/o:amazon:linux:2023, p-cpe:/a:amazon:linux:samba-client, p-cpe:/a:amazon:linux:python3-samba-test, p-cpe:/a:amazon:linux:samba-common-tools, p-cpe:/a:amazon:linux:samba-devel, p-cpe:/a:amazon:linux:samba-common, p-cpe:/a:amazon:linux:libsmbclient-devel, p-cpe:/a:amazon:linux:libnetapi-devel, p-cpe:/a:amazon:linux:python3-samba-dc-debuginfo, p-cpe:/a:amazon:linux:samba-dc-libs, p-cpe:/a:amazon:linux:python3-samba-dc, p-cpe:/a:amazon:linux:samba-krb5-printing-debuginfo, p-cpe:/a:amazon:linux:samba-winbind-modules, p-cpe:/a:amazon:linux:samba-test-debuginfo, p-cpe:/a:amazon:linux:python3-samba-devel

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

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 10/30/2023

Vulnerability Publication Date: 10/10/2023

Reference Information

CVE: CVE-2023-3961, CVE-2023-4091

IAVA: 2023-A-0535