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CVE-2021-20134

Published: Dec 30, 2021Updated: Nov 21, 2024 Sources: CVE List NVDCWE-22

Description

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 Vector Breakdown

AV:AAC:LPR:HUI:NS:CC:HI:HA:H
Exploitability
AV:AAttack Vector
Adjacent
AC:LAttack Complexity
Low
PR:HPrivileges Required
High
UI:NUser Interaction
None
Scope
S:CScope
Changed
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High

Weaknesses

Affected Products

Attack Graph

Products CVE Techniques Tactics

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Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

MITRE ATT&CK

2 techniques
Collection
Discovery
View detailed technique mapping

References

Timeline

Published
Dec 30, 2021
Last Updated
Nov 21, 2024

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