Multiple vulnerabilities in Samba

Published: 2021-03-24

Risk	High
Patch available	YES
Number of vulnerabilities	2
CVE-ID	CVE-2020-27840 CVE-2021-20277
CWE-ID	CWE-122 CWE-125
Exploitation vector	Network
Public exploit	N/A
Vulnerable software	Samba Server applications / Directory software, identity management
Vendor	Samba

Security Bulletin

This security bulletin contains information about 2 vulnerabilities.

1) Heap-based buffer overflow

EUVDB-ID: #VU51702

Risk: High

CVSSv4.0: 8.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2020-27840

CWE-ID: CWE-122 - Heap-based Buffer Overflow

Exploit availability: No

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error when processing DNs inside bind requests. A remote attacker can send specially crafted LDAP request to Samba AD DC LDAP server, trigger heap-based buffer overflow and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Samba: 4.0.0 - 4.14.0

CPE2.3

External links

https://www.samba.org/samba/security/CVE-2020-27840.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) Out-of-bounds read

EUVDB-ID: #VU51701

Risk: Medium

CVSSv4.0: 4.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-20277

CWE-ID: CWE-125 - Out-of-bounds read