VDB-127271 · CVE-2018-16851 · USN-3827-1

Samba up to 4.7.11/4.8.6/4.9.2 LDAP Service null pointer dereference

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5.7	$0-$5k	0.00

Summaryinfo

A vulnerability marked as problematic has been reported in Samba up to 4.7.11/4.8.6/4.9.2. Affected by this issue is some unknown functionality of the component LDAP Service. The manipulation leads to null pointer dereference. This vulnerability is documented as CVE-2018-16851. The attack can be initiated remotely. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Samba up to 4.7.11/4.8.6/4.9.2 (File Transfer Software). This issue affects an unknown code of the component LDAP Service. The manipulation with an unknown input leads to a null pointer dereference vulnerability. Using CWE to declare the problem leads to CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. Impacted is availability. The summary by CVE is:

Samba from version 4.0.0 and before versions 4.7.12, 4.8.7, 4.9.3 is vulnerable to a denial of service. During the processing of an LDAP search before Samba's AD DC returns the LDAP entries to the client, the entries are cached in a single memory object with a maximum size of 256MB. When this size is reached, the Samba process providing the LDAP service will follow the NULL pointer, terminating the process. There is no further vulnerability associated with this issue, merely a denial of service.

The bug was discovered 11/28/2018. The weakness was released 11/28/2018 as confirmed bug report (Bugzilla). It is possible to read the advisory at bugzilla.redhat.com. The identification of this vulnerability is CVE-2018-16851 since 09/11/2018. The attack may be initiated remotely. A simple authentication is needed for exploitation. The technical details are unknown and an exploit is not publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 119246 (FreeBSD : samba -- multiple vulnerabilities (54976998-f248-11e8-81e2-005056a311d1)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family FreeBSD Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 197311 (Ubuntu Security Notification for Samba Vulnerabilities (USN-3827-1)).

Upgrading to version 4.7.12, 4.8.7 or 4.9.3 eliminates this vulnerability. A possible mitigation has been published even before and not after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (119246) and SecurityFocus (BID 106027†). Entries connected to this vulnerability are available at VDB-127263, VDB-127270, VDB-127272 and VDB-127273. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

File Transfer Software

Name

Samba

Version

License

open-source

Website

Product: https://www.samba.org/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.8
VulDB Meta Temp Score: 5.7

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔍

CNA Base Score: 6.5
CNA Vector (Red Hat, Inc.): 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 119246
Nessus Name: FreeBSD : samba -- multiple vulnerabilities (54976998-f248-11e8-81e2-005056a311d1)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Samba 4.7.12/4.8.7/4.9.3

Timelineinfo

08/14/2018 🔍
09/11/2018 +28 days 🔍
11/27/2018 +77 days 🔍
11/28/2018 +1 days 🔍
11/28/2018 +0 days 🔍
11/28/2018 +0 days 🔍
11/28/2018 +0 days 🔍
11/29/2018 +1 days 🔍
06/12/2023 +1656 days 🔍

Sourcesinfo

Product: samba.org

Advisory: USN-3827-1
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2018-16851 (🔍)
GCVE (CVE): GCVE-0-2018-16851
GCVE (VulDB): GCVE-100-127271

OVAL: 🔍

SecurityFocus: 106027 - Samba CVE-2018-16851 Remote Denial of Service Vulnerability

See also: 🔍

Entryinfo

Created: 11/29/2018 07:50
Updated: 06/12/2023 08:08
Changes: 11/29/2018 07:50 (75), 04/15/2020 20:56 (5), 06/12/2023 08:06 (4), 06/12/2023 08:08 (12)
Complete: 🔍
Cache ID: 216::103