CVE-2018-5721

Public Exploit

Description

Stack-based buffer overflow in the ej_update_variables function in router/httpd/web.c on ASUS routers (when using software from https://github.com/RMerl/asuswrt-merlin) allows web authenticated attackers to execute code via a request that updates a setting. In ej_update_variables, the length of the variable action_script is not checked, as long as it includes a "_wan_if" substring.

Category

8.8
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 1.82% Top 20%
Third-Party Advisory w0lfzhang.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
http://www.w0lfzhang.com/2018/01/17/ASUS-router-stack-overflow-in-http-server/ third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2018-5721?
CVE-2018-5721 has been scored as a high severity vulnerability.
How to fix CVE-2018-5721?
To fix CVE-2018-5721, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2018-5721 being actively exploited in the wild?
It is possible that CVE-2018-5721 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~2% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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