Path Traversal in Dlink Dir-2640-Us
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.
Vulnerability class: Path Traversal (Directory Traversal)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.4 (High). Vector: CVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.075 (94.3th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 94th percentile — 94.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.075 · newest: 0.075 · change: 0.000
Affected products
- Dlink Dir-2640-Us
- Dlink Dir-2640-Us Firmware
- Quagga Services On D-Link Dir-2640 Routers — versions <= 1.11B02
Weakness classification (CWE)
References
- www.tenable.com/security/research/tra-2021-44 (Exploit, Third Party Advisory)
Frequently asked questions
- What is CVE-2021-20134?
- CVE-2021-20134 is a high-severity vulnerability in Dlink Dir-2640-Us, classified under Path Traversal. CVSS score: 8.4/10. Published 2021-12-30.
- How severe is CVE-2021-20134?
- High severity. CVSS v3 base score is 8.4 out of 10.