CVE-2021-28839
CVSS v3
7.5
HIGH
EPSS Score
1.4 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
Null Pointer Dereference vulnerability exists in D-Link DAP-2310 2.07.RC031, DAP-2330 1.07.RC028, DAP-2360 2.07.RC043, DAP-2553 3.06.RC027, DAP-2660 1.13.RC074, DAP-2690 3.16.RC100, DAP-2695 1.17.RC063, DAP-3320 1.01.RC014 and DAP-3662 1.01.RC022 in the upload_certificate function of sbin/httpd binary. When the binary handle the specific HTTP GET request, the strrchr in the upload_certificate function would take NULL as first argument, and incur the NULL pointer dereference vulnerability.
Technical details
- Published
- 2021-08-10
Frequently asked questions
What is CVE-2021-28839?
Null Pointer Dereference vulnerability exists in D-Link DAP-2310 2.07.RC031, DAP-2330 1.07.RC028, DAP-2360 2.07.RC043, DAP-2553 3.06.RC027, DAP-2660 1.13.RC074, DAP-2690 3.16.RC100, DAP-2695 1.17.RC063, DAP-3320 1.01.RC014 and DAP-3662 1.01.RC022 in the upload_certificate function of sbin/httpd binary. When the binary handle the specific HTTP GET request, the strrchr in the upload_certificate function would take NULL as first argument, and incur the NULL pointer dereference vulnerability.
Is CVE-2021-28839 actively exploited?
Active exploitation of CVE-2021-28839 has not been confirmed. Its EPSS score was 1.4% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-28839?
CVE-2021-28839 has a CVSS v3 base score of 7.5 (HIGH severity).
Is CVE-2021-28839 affecting your environment?
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