CVE-2021-39509

Public Exploit

Description

An issue was discovered in D-Link DIR-816 DIR-816A2_FWv1.10CNB05_R1B011D88210 The HTTP request parameter is used in the handler function of /goform/form2userconfig.cgi route, which can construct the user name string to delete the user function. This can lead to command injection through shell metacharacters.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 21.23% Top 5%
Vendor Advisory dlink.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://www.dlink.com/en/security-bulletin/ vendor advisory
https://github.com/doudoudedi/main-DIR-816_A2_Command-injection/blob/main/injection.md third party advisory exploit
https://github.com/doudoudedi/main-DIR-816_A2_Command-injection third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-39509?
CVE-2021-39509 has been scored as a critical severity vulnerability.
How to fix CVE-2021-39509?
To fix CVE-2021-39509, 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-2021-39509 being actively exploited in the wild?
It is possible that CVE-2021-39509 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~21% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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