#VU29486 Input validation error in Samba - CVE-2020-14303

Vulnerability identifier: #VU29486

Vulnerability risk: Medium

CVSSv4.0: 7.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/U:Green]

CVE-ID: CVE-2020-14303

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Samba
Server applications / Directory software, identity management

Vendor: Samba

Description

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

The vulnerability exists due to insufficient validation of UDp packets with 0 length data  in Samba. A remote attacker can send a specially crafted UDP packet to port 137/TCP and perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Samba: 4.0.0 - 4.0.26, 4.1.0 - 4.12.3, 4.2.0 - 4.2.14, 4.3.0 - 4.3.13, 4.4.0 rc4 - 4.4.16, 4.5.0 - 4.5.16, 4.6.0 - 4.6.16, 4.7.0 - 4.7.12, 4.8.0 - 4.8.12, 4.9.0 - 4.9.18

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External links
https://www.samba.org/samba/security/CVE-2020-14303.html

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Q & A

Can this vulnerability be exploited remotely?

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