CVE-2021-28839

mediumpriority · track · 30EPSS 0.014 · 72 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.38% (72nd) EPSS

CVSS 5 · medium

Is it mine?

10 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-28

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.

cvss

Technical severity, 0–10. One row per scoring source.

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5

v2.05mediumAV:N/AC:L/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-476USprimary

affected products (10)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
dlink dap-2310 firmware= 2.0.7.rc031nvdUScpe:2.3:o:dlink:dap-2310_firmware:*:*:*:*:*:*:*:*
dlink dap-2330 firmware= 1.07.rc028nvdUScpe:2.3:o:dlink:dap-2330_firmware:*:*:*:*:*:*:*:*
dlink dap-2360 firmware= 2.07.rc043nvdUScpe:2.3:o:dlink:dap-2360_firmware:*:*:*:*:*:*:*:*
dlink dap-2553 firmware= 3.06.rc027nvdUScpe:2.3:o:dlink:dap-2553_firmware:*:*:*:*:*:*:*:*
dlink dap-2660 firmware= 1.13.rc074nvdUScpe:2.3:o:dlink:dap-2660_firmware:*:*:*:*:*:*:*:*
dlink dap-2690 firmware= 3.16.rc100nvdUScpe:2.3:o:dlink:dap-2690_firmware:*:*:*:*:*:*:*:*
dlink dap-2695 firmware= 1.17.rc063nvdUScpe:2.3:o:dlink:dap-2695_firmware:*:*:*:*:*:*:*:*
dlink dap-3320 firmware= 1.01.rc014nvdUScpe:2.3:o:dlink:dap-3320_firmware:*:*:*:*:*:*:*:*
dlink dap-3662 firmware= 1.01.rc022nvdUScpe:2.3:o:dlink:dap-3662_firmware:*:*:*:*:*:*:*:*

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2021-08-10modified 2026-06-17

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+8817 more

references (10)

External citations — patches, advisories, analysis.

scry

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