CVE-2018-3953
What it is
Devices in the Linksys ESeries line of routers (Linksys E1200 Firmware Version 2.0.09 and Linksys E2500 Firmware Version 3.0.04) are susceptible to OS command injection vulnerabilities due to improper filtering of data passed to and retrieved from NVRAM. Data entered into the 'Router Name' input field through the web portal is submitted to apply.cgi as the value to the 'machine_name' POST parameter. When the 'preinit' binary receives the SIGHUP signal, it enters a code path that continues until it reaches offset 0x0042B5C4 in the 'start_lltd' function. Within the 'start_lltd' function, a 'nvram_get' call is used to obtain the value of the user-controlled 'machine_name' NVRAM entry. This value is then entered directly into a command intended to write the host name to a file and subsequently executed.
At a glance
- Exploitability
- Can be exploited over the network with an admin-level account. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 13.5% chance of exploitation in the next 30 days (EPSS). Higher than most.
- Fix
- No patch or advisory is linked yet. Look at mitigations or restrict exposure.
Timeline
- 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: 13.5% in the next 30 days (EPSS).
- Severity: 7.2 HIGH (CVSS).
- Fix: none linked yet, which raises it.
Details
- Published
- Last modified
- Exploit probability
- 13.5% · EPSS, next 30 days
- Weakness
- CWE-78 · OS command injection
- Record status
- Modified
Affected
- Linksys e1200 Firmware 2.0.09
- Linksys e2500 Firmware 3.0.04
Attack profile CVSS 3.1 · 7.2
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- High
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/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-2018-3953.md and follow it. Check whether this project is affected by CVE-2018-3953. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
