CVE-2021-31800 Information

Description

Multiple path traversal vulnerabilities exist in smbserver.py in Impacket through 0.9.22. An attacker that connects to a running smbserver instance can list and write to arbitrary files via ../ directory traversal. This could potentially be abused to achieve arbitrary code execution by replacing /etc/shadow or an SSH authorized key.

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Reference

https://github.com/SecureAuthCorp/impacket/blob/cb6d43a677c338db930bc4e9161620832c1ec624/impacket/smbserver.py#L2008 https://github.com/SecureAuthCorp/impacket/releases https://github.com/SecureAuthCorp/impacket/blob/cb6d43a677c338db930bc4e9161620832c1ec624/impacket/smbserver.py#L876 https://github.com/SecureAuthCorp/impacket/blob/cb6d43a677c338db930bc4e9161620832c1ec624/impacket/smbserver.py#L2958 https://github.com/SecureAuthCorp/impacket/commit/49c643bf66620646884ed141c94e5fdd85bcdd2f https://github.com/SecureAuthCorp/impacket/blob/cb6d43a677c338db930bc4e9161620832c1ec624/impacket/smbserver.py#L3485 https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UF56LYB27LHEIFJTFHU3M75NMNNK2SCG/ https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/IPXDPWCAPVX3UWYZ3N2T5OLBSBBUHJP6/ https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/KRV2C5DATXBHG6TF6CEEX54KZ75THQS3/

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

HIGH

Base Severity

9.8