CVE-2021-20134: Path Traversal
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.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2021-20134?
CVE-2021-20134 has a medium severity rating due to its potential to allow authenticated attackers to manipulate log files on affected devices.
How do I fix CVE-2021-20134?
To fix CVE-2021-20134, upgrade the D-Link DIR-2640 firmware to a version later than 1.11B02.
What types of devices are affected by CVE-2021-20134?
CVE-2021-20134 affects D-Link DIR-2640 routers running firmware version 1.11B02 or earlier.
Can CVE-2021-20134 be exploited remotely?
Yes, CVE-2021-20134 can be exploited remotely by an authenticated attacker.
What is the impact of CVE-2021-20134?
The impact of CVE-2021-20134 is the potential for unauthorized file manipulation on the router's filesystem.