CVE-2021-20134

Quagga Services on D-Link DIR-2640 less than or equal to version 1.11B02 are affected by an absolute path traversal vulnerability that allows a remote, authenticated attacker to set an arbitrary file on the router's filesystem as the log file used by either Quagga service (zebra or ripd). Subsequent log messages will be appended to the file, prefixed by a timestamp and some logging metadata. Remote code execution can be achieved by using this vulnerability to append to a shell script on the router's filesystem, and then awaiting or triggering the execution of that script. A remote, unauthenticated root shell can easily be obtained on the device in this fashion.

CVSS v3.0 8.4 HIGH
CVSS v2.0 7.4 HIGH

8.4^/10

CVSS v3.0 : HIGH

Vector :

Exploitability : 1.7 / Impact : 6.0

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

7.4^/10

CVSS v2.0 : HIGH

Vector : AV:A/AC:M/Au:S/C:C/I:C/A:C

Exploitability : 4.4 / Impact : 10.0

Access Vector ADJACENT_NETWORK

Access Complexity MEDIUM

Authentication SINGLE

Confidentiality Impact COMPLETE

Integrity Impact COMPLETE

Availability Impact COMPLETE

References

Link	Resource
https://www.tenable.com/security/research/tra-2021-44	Exploit Third Party Advisory

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Configurations

Configuration 1 (hide)

AND

cpe:2.3:o:dlink:dir-2640-us_firmware:*:*:*:*:*:*:*:*

cpe:2.3:h:dlink:dir-2640-us:-:*:*:*:*:*:*:*

Information

Published : 2021-12-30 14:15

Updated : 2022-01-12 11:52

NVD link : CVE-2021-20134

Mitre link : CVE-2021-20134

JSON object : View

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

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Products Affected

dlink

dir-2640-us_firmware
dir-2640-us

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