CVE-2018-16838

sssd: improper implementation of GPOs due to too restrictive permissions

Severity Score

5.4

*CVSS v3

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

A flaw was found in sssd Group Policy Objects implementation. When the GPO is not readable by SSSD due to a too strict permission settings on the server side, SSSD will allow all authenticated users to login instead of denying access.

Se ha encontrado un error en la implementación de sssd Group Policy Objects. Cuando el GPO no puede ser leído por SSSD debido a ajustes de permisos demasiado estrictos del lado del servidor, SSSD permitirá que todos los usuarios autenticados inicien sesión, en lugar de denegar el acceso.

Jakub Hrozek discovered that SSSD incorrectly handled file permissions. A local attacker could possibly use this issue to read the sudo rules available for any user. This issue only affected Ubuntu 18.04 LTS. It was discovered that SSSD incorrectly handled Group Policy Objects. When SSSD is configured with too strict permissions causing the GPO to not be readable, SSSD will allow all authenticated users to login instead of being denied, contrary to expectations. This issue only affected Ubuntu 18.04 LTS. Various other issues were also addressed.

*Credits: N/A

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

Low

Availability

None

Attack Vector

Network

Attack Complexity

Low

Authentication

Single

Confidentiality

Partial

Integrity

Partial

Availability

None

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2018-09-11 CVE Reserved
2019-03-25 CVE Published
2025-02-13 CVE Updated
2025-06-30 EPSS Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-269: Improper Privilege Management
CWE-284: Improper Access Control

CAPEC

References (9)

URL	Tag	Source
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-16838	Issue Tracking
https://lists.debian.org/debian-lts-announce/2023/05/msg00028.html

URL	Date	SRC

URL	Date	SRC

URL	Date	SRC
http://lists.opensuse.org/opensuse-security-announce/2019-06/msg00042.html	2023-05-29
http://lists.opensuse.org/opensuse-security-announce/2019-06/msg00051.html	2023-05-29
https://access.redhat.com/errata/RHSA-2019:2177	2023-05-29
https://access.redhat.com/errata/RHSA-2019:2437	2023-05-29
https://access.redhat.com/errata/RHSA-2019:3651	2023-05-29
https://access.redhat.com/security/cve/CVE-2018-16838	2019-11-05
https://bugzilla.redhat.com/show_bug.cgi?id=1640820	2019-11-05

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Fedoraproject Search vendor "Fedoraproject"		Sssd Search vendor "Fedoraproject" for product "Sssd"				-		-		Affected
Redhat Search vendor "Redhat"		Enterprise Linux Search vendor "Redhat" for product "Enterprise Linux"				7.0 Search vendor "Redhat" for product "Enterprise Linux" and version "7.0"		-		Affected