Multiple vulnerabilities in Samba

1) Improper Authorization

EUVDB-ID: #VU81875

Risk: High

CVSSv3.1: 7.9 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2023-3961

CWE-ID: CWE-285 - Improper Authorization

Exploit availability: No

Description

The vulnerability allows a remote attacker to compromise the affected system.

The vulnerability exists due to improper input validation when handling client pipe names. A remote attacker can provide a specially crafted pipe name containing directory traversal characters and force Samba to connect to Unix domain sockets outside of the private directory meant to restrict the services a client could connect to.The connection to Unix domain sockets is performed as root, which means that if client sends a pipe name that resolved to an external service using an existing Unix domain socket, the client is able to connect to it without any filesystem restrictions.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Samba: 4.16.0 - 4.19.0

External links

http://www.samba.org/samba/security/CVE-2023-3961.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

2) Information disclosure

EUVDB-ID: #VU81874

Risk: Medium

CVSSv3.1: 5.9 [CVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2023-4154

CWE-ID: CWE-200 - Information exposure

Exploit availability: No

Description

The vulnerability allows a remote user to gain access to potentially sensitive information.

The vulnerability exists due to a design error in Samba's implementation of the DirSync control, which can allow replication of critical domain passwords and secrets by Active Directory accounts authorized to do some replication, but not to replicate sensitive attributes. A remote user can obtain sensitive information from the AD DC and compromise the Active Directory.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Samba: 4.0.0 - 4.19.0

External links

http://www.samba.org/samba/security/CVE-2023-4154.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated privileged user via the local network (LAN).

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

3) Permissions, Privileges, and Access Controls

EUVDB-ID: #VU81872

Risk: Low

CVSSv3.1: 3.8 [CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2023-4091

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

Exploit availability: No

Description

The vulnerability allows a remote user to truncate read-only files.

The vulnerability exists due to an error in the way SMB protocol implementation in Samba handles file operations. A remote user can request read-only access to files and then truncate them to 0 bytes by opening files with OVERWRITE disposition when using the acl_xattr Samba VFS module with the smb.conf setting "acl_xattr:ignore system acls = yes".

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Samba: 1.9.16 - 4.19.0

External links

http://www.samba.org/samba/security/CVE-2023-4091.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

4) Resource management error

EUVDB-ID: #VU81871

Risk: Medium

CVSSv3.1: 5.7 [CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2023-42669

CWE-ID: CWE-399 - Resource Management Errors

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to inclusion of the "rpcecho" server into production build, which can call sleep() on AD DC. A remote user can request the server block using the "rpcecho" server and perform a denial of service (DoS) attack.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Samba: 4.0.0 - 4.19.0

External links

http://www.samba.org/samba/security/CVE-2023-42669.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

5) Resource management error

EUVDB-ID: #VU81867

Risk: Medium

CVSSv3.1: 5.7 [CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2023-42670

CWE-ID: CWE-399 - Resource Management Errors

Exploit availability: No

Description

The vulnerability allows a remote user to perform a denial of service (DoS) attack.

The vulnerability exists due to improper management of internal resources within the application when Samba RPC server is under load, which can lead to incorrect start of servers not built for the AD DC. A remote user can cause a high load to Samba RPC server and perform a denial of service (DoS) attack.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Samba: 4.16.0 - 4.19.0

External links

http://www.samba.org/samba/security/CVE-2023-42670.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.