EulerOS Virtualization 3.0.6.0 : samba (EulerOS-SA-2020-1746)

Medium Nessus Plugin ID 137965

Synopsis

The remote EulerOS Virtualization host is missing multiple security updates.

Description

According to the versions of the samba packages installed, the EulerOS Virtualization installation on the remote host is affected by the following vulnerabilities :

- All Samba versions 4.x.x before 4.9.17, 4.10.x before 4.10.11 and 4.11.x before 4.11.3 have an issue, where the S4U (MS-SFU) Kerberos delegation model includes a feature allowing for a subset of clients to be opted out of constrained delegation in any way, either S4U2Self or regular Kerberos authentication, by forcing all tickets for these clients to be non-forwardable. In AD this is implemented by a user attribute delegation_not_allowed (aka not-delegated), which translates to disallow-forwardable. However the Samba AD DC does not do that for S4U2Self and does set the forwardable flag even if the impersonated client has the not-delegated flag set.(CVE-2019-14870)

- All Samba versions 4.x.x before 4.9.17, 4.10.x before 4.10.11 and 4.11.x before 4.11.3 have an issue, where the (poorly named) dnsserver RPC pipe provides administrative facilities to modify DNS records and zones. Samba, when acting as an AD DC, stores DNS records in LDAP. In AD, the default permissions on the DNS partition allow creation of new records by authenticated users. This is used for example to allow machines to self-register in DNS. If a DNS record was created that case-insensitively matched the name of the zone, the ldb_qsort() and dns_name_compare() routines could be confused into reading memory prior to the list of DNS entries when responding to DnssrvEnumRecords() or DnssrvEnumRecords2() and so following invalid memory as a pointer.(CVE-2019-14861)

- All samba versions 4.9.x before 4.9.18, 4.10.x before 4.10.12 and 4.11.x before 4.11.5 have an issue where if it is set with 'log level = 3' (or above) then the string obtained from the client, after a failed character conversion, is printed. Such strings can be provided during the NTLMSSP authentication exchange. In the Samba AD DC in particular, this may cause a long-lived process(such as the RPC server) to terminate. (In the file server case, the most likely target, smbd, operates as process-per-client and so a crash there is harmless).(CVE-2019-14907)

- There is an issue in all samba 4.11.x versions before 4.11.5, all samba 4.10.x versions before 4.10.12 and all samba 4.9.x versions before 4.9.18, where the removal of the right to create or modify a subtree would not automatically be taken away on all domain controllers.(CVE-2019-14902)

- A flaw was found in samba's Heimdal KDC implementation, versions 4.8.x up to, excluding 4.8.12, 4.9.x up to, excluding 4.9.8 and 4.10.x up to, excluding 4.10.3, when used in AD DC mode. A man in the middle attacker could use this flaw to intercept the request to the KDC and replace the user name (principal) in the request with any desired user name (principal) that exists in the KDC effectively obtaining a ticket for that principal.(CVE-2018-16860)

- A use-after-free flaw was found in the way samba AD DC LDAP servers, handled 'Paged Results' control is combined with the 'ASQ' control. A malicious user in a samba AD could use this flaw to cause denial of service. This issue affects all samba versions before 4.10.15, before 4.11.8 and before 4.12.2.(CVE-2020-10700)

- A use-after-free flaw was found in the way samba AD DC LDAP servers, handled 'Paged Results' control is combined with the 'ASQ' control. A malicious user in a samba AD could use this flaw to cause denial of service. This issue affects all samba versions before 4.10.15, before 4.11.8 and before 4.12.2.(CVE-2020-10700)

Note that Tenable Network Security has extracted the preceding description block directly from the EulerOS security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

Solution

Update the affected samba packages.

See Also

http://www.nessus.org/u?68ff6903

Plugin Details

Severity: Medium

ID: 137965

File Name: EulerOS_SA-2020-1746.nasl

Version: 1.2

Type: local

Published: 2020/07/01

Updated: 2020/07/06

Dependencies: 12634

Risk Information

Risk Factor: Medium

CVSS v2.0

Base Score: 6.4

Temporal Score: 4.7

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

Temporal Vector: CVSS2#E:U/RL:OF/RC:C

CVSS v3.0

Base Score: 5.4

Temporal Score: 4.7

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

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

Vulnerability Information

CPE: p-cpe:/a:huawei:euleros:libsmbclient, p-cpe:/a:huawei:euleros:libwbclient, p-cpe:/a:huawei:euleros:samba-client-libs, p-cpe:/a:huawei:euleros:samba-common, p-cpe:/a:huawei:euleros:samba-common-libs, p-cpe:/a:huawei:euleros:samba-common-tools, p-cpe:/a:huawei:euleros:samba-libs, cpe:/o:huawei:euleros:uvp:3.0.6.0

Required KB Items: Host/local_checks_enabled, Host/cpu, Host/EulerOS/release, Host/EulerOS/rpm-list, Host/EulerOS/uvp_version

Exploit Ease: No known exploits are available

Patch Publication Date: 2020/06/30

Reference Information

CVE: CVE-2018-16860, CVE-2019-14861, CVE-2019-14870, CVE-2019-14902, CVE-2019-14907, CVE-2020-10700