What’s Vulnerable › Vulnerabilities

CVE-2021-39509

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 5.1% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2021-08-24 · updated 2026-06-17
• Weakness: CWE-77

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.

Affected products

• D-Link DIR-816: 1.10cnb05_r1b011d88210

References

• https://github.com/doudoudedi/main-DIR-816_A2_Command-injection
• https://github.com/doudoudedi/main-DIR-816_A2_Command-injection/blob/main/injection.md
• https://www.dlink.com/en/security-bulletin/
• https://github.com/doudoudedi/main-DIR-816_A2_Command-injection
• https://github.com/doudoudedi/main-DIR-816_A2_Command-injection/blob/main/injection.md
• https://www.dlink.com/en/security-bulletin/

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