CVE-2021-20134
What it is
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.
At a glance
- Exploitability
- Can be exploited from the same network segment with an admin-level account. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 7.8% chance of exploitation in the next 30 days (EPSS).
- Fix
- No patch or advisory is linked yet. Look at mitigations or restrict exposure.
Timeline
- ReservedThe CVE id was reserved by its CNA
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 7.8% in the next 30 days (EPSS).
- Severity: 8.4 HIGH (CVSS).
- Fix: none linked yet, which raises it.
Details
- Published
- Last modified
- Exploit probability
- 7.8% · EPSS, next 30 days
- Weakness
- CWE-22 · Path traversal
- Record status
- Modified
Affected
- Dlink dir-2640-us Firmware ≤ 1.11b02
Attack profile CVSS 3.1 · 8.4
- Attack vector
- Adjacent network
- Complexity
- Low
- Privileges needed
- High
- User interaction
- None
- Scope
- Changed
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2021-20134.md and follow it. Check whether this project is affected by CVE-2021-20134. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
