CVE-2021-39509 json
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…
published 2021-08-24 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-25866
- cvss
- 9.8
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 5.1%
- EPSS 5.1% chance of exploitation in 30 days, percentile 92%
- public exploits
- 0
- none known
Summary
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.
Exploit prediction
5.10% chance of exploitation in the next 30 days, higher than 92% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/doudoudedi/main-DIR-816_A2_Command-injection/blob/main/injection.md referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 7.5 | AV:N/AC:L/Au:N/C:P/I:P/A:P |
Classification
- Weakness
-
- CWE-77 Improper Neutralization of Special Elements used in a Command
References
-
github.com
/doudoudedi/main-DIR-816_A2_Command-injection/blob/main/injection.md
exploit, third-party-advisory
-
dlink.com
/en/security-bulletin/
vendor-advisory
-
github.com
/doudoudedi/main-DIR-816_A2_Command-injection
third-party-advisory
Sources
- CVE List CVE-2021-39509
- NVD CVE-2021-39509
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