Buffalo Router Path Traversal (CVE-2021-20090)

critical Nessus Plugin ID 154981
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Synopsis

The remote router hosts a web server that is affected by a directory traversal vulnerability.

Description

The remote web server hosted on the Buffalo router is affected by a directory traversal vulnerability due to an improper access restriction. An unauthenticated, remote attacker can exploit this, by sending a URI that contains directory traversal characters, to disclose the contents of files located outside of the server's restricted path.

Solution

Apply the appropriate firmware update for the device.

See Also

https://www.tenable.com/security/research/tra-2021-13

https://www.buffalo.jp/news/detail/20211004-02.html

Plugin Details

Severity: Critical

ID: 154981

File Name: buffalo_CVE-2021-20090_path_traversal.nbin

Version: 1.7

Type: remote

Family: CGI abuses

Published: 11/9/2021

Updated: 12/20/2021

Dependencies: buffalo_www_detect.nbin

Risk Information

CVSS Score Source: CVE-2021-20090

VPR

Risk Factor: Critical

Score: 9.4

CVSS v2

Risk Factor: High

Base Score: 7.5

Temporal Score: 5.5

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P

Temporal Vector: CVSS2#E:U/RL:OF/RC:C

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 8.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

Required KB Items: installed_sw/Buffalo WWW

Exploit Ease: No known exploits are available

Patch Publication Date: 4/26/2021

Vulnerability Publication Date: 4/26/2021

Reference Information

CVE: CVE-2021-20090