CVE-2021-43517
CVSS v3
9.8
CRITICAL
EPSS Score
1.7 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
FOSCAM Camera FI9805E with firmware V4.02.R12.00018510.10012.143900.00000 contains a backdoor that opens Telnet port when special command is sent on port 9530.
Technical details
- Published
- 2022-04-08
Frequently asked questions
What is CVE-2021-43517?
FOSCAM Camera FI9805E with firmware V4.02.R12.00018510.10012.143900.00000 contains a backdoor that opens Telnet port when special command is sent on port 9530.
Is CVE-2021-43517 actively exploited?
Active exploitation of CVE-2021-43517 has not been confirmed. Its EPSS score was 1.7% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-43517?
CVE-2021-43517 has a CVSS v3 base score of 9.8 (CRITICAL severity).
Is CVE-2021-43517 affecting your environment?
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