Critical severity · published Aug 24, 2021
CVE-2021-39509
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,…
9.8
CVSS
5.1%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)5.1% · higher than 92% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DF
Dir-816 Firmware · Dlink
1.10cnb05_r1b011d88210 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-39509
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-39509
Third Party Advisory
https://github.com/doudoudedi/main-DIR-816_A2_Command-injection
Exploit
https://github.com/doudoudedi/main-DIR-816_A2_Command-injection/blob/main/injection.md
Vendor Advisory
https://www.dlink.com/en/security-bulletin/
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