Debian update for samba

1) Out-of-bounds write

EUVDB-ID: #VU60186

Risk: High

CVSSv3.1: 8.9 [CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:P/RL:O/RC:C]

CVE-ID: CVE-2021-44142

CWE-ID: CWE-787 - Out-of-bounds write

Exploit availability: Yes

Description

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a boundary error when processing EA metadata while opening files in smbd within the VFS Samba module (vfs_fruit). A remote attacker with ability to write to file's extended attributes can trigger an out-of-bounds write and execute arbitrary code with root privileges.

Note, the vulnerability in vfs_fruit exists in the default configuration of the fruit VFS module using fruit:metadata=netatalk or fruit:resource=file.

Mitigation

Update samba package to one of the following versions: 2:4.9.5+dfsg-5+deb10u3, 2:4.13.13+dfsg-1~deb11u3.

Vulnerable software versions

samba (Debian package): 2:4.9.0+dfsg-1 - 2:4.13.13+dfsg-1~deb11u2

External links

http://www.debian.org/security/2022/dsa-5071

Q & A

Can this vulnerability be exploited remotely?

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

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.

2) Insufficient verification of data authenticity

EUVDB-ID: #VU60185

Risk: Low

CVSSv3.1: 4.1 [CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2022-0336

CWE-ID: CWE-345 - Insufficient Verification of Data Authenticity

Exploit availability: No

Description

The vulnerability allows a local user to impersonate arbitrary services.

The vulnerability exists due to Samba AD DC relies only on SPN (service principals name) to identify services on the network. An attacker with ability to modify SPNs can bypass implemented protection and cause a denial of service condition by adding an SPN that matches an existing service or impersonate services on the network.

Mitigation

Update samba package to one of the following versions: 2:4.9.5+dfsg-5+deb10u3, 2:4.13.13+dfsg-1~deb11u3.

Vulnerable software versions

samba (Debian package): 2:4.9.0+dfsg-1 - 2:4.13.13+dfsg-1~deb11u2

External links

http://www.debian.org/security/2022/dsa-5071

Q & A

Can this vulnerability be exploited remotely?

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

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: #VU58097

Risk: Medium

CVSSv3.1: 7.1 [CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-25717

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

Exploit availability: No

Description

The vulnerability allows a remote attacker to escalate privileges on the system.

The vulnerability exists due to the Windows Active Directory (AD) domains have by default a feature to allow users to create computer accounts. A remote authenticated attacker can create such account with elevated privileges on the system.

Mitigation

Update samba package to one of the following versions: 2:4.9.5+dfsg-5+deb10u3, 2:4.13.13+dfsg-1~deb11u3.

Vulnerable software versions

samba (Debian package): 2:4.9.0+dfsg-1 - 2:4.13.13+dfsg-1~deb11u2

External links

http://www.debian.org/security/2022/dsa-5071

Q & A

Can this vulnerability be exploited remotely?

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

Is there known malware, which exploits this vulnerability?

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