CVE-2021-28838

Name: CVE-2021-28838
Creator: NVD / NIST
Published: 2021-08-10T18:15:07.137+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 2.16%

Last modified Jun 17, 2026

CVE-2021-28838 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. Null pointer dereference vulnerability in D-Link DAP-2310 2,10RC039, DAP-2330 1.10RC036 BETA, DAP-2360 2.10RC055, DAP-2553 3.10rc039 BETA, DAP-2660 1.15rc131b, DAP-2690 3.20RC115 BETA, DAP-2695 1.20RC093, DAP-3320 1.05RC027 BETA and DAP-3662 1.05rc069 in the sbin/httpd binary. The crash happens at the `atoi' operation when a specific network package are sent to the httpd binary.. EPSS estimates a 2.16% chance of exploitation in the next 30 days.

Description

Null pointer dereference vulnerability in D-Link DAP-2310 2,10RC039, DAP-2330 1.10RC036 BETA, DAP-2360 2.10RC055, DAP-2553 3.10rc039 BETA, DAP-2660 1.15rc131b, DAP-2690 3.20RC115 BETA, DAP-2695 1.20RC093, DAP-3320 1.05RC027 BETA and DAP-3662 1.05rc069 in the sbin/httpd binary. The crash happens at the `atoi' operation when a specific network package are sent to the httpd binary.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

2.16%

79.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-476

Affected Software

Vendor	Product	Versions	Update
Dlink	Dap-2310 Firmware	<= 2.10rc039	—
Dlink	Dap-2330 Firmware	< 1.10rc036	—
Dlink	Dap-2330 Firmware	1.10rc036	Beta
Dlink	Dap-2360 Firmware	<= 2.10rc055	—
Dlink	Dap-2553 Firmware	< 3.10rc039	—
Dlink	Dap-2553 Firmware	3.10rc039	Beta
Dlink	Dap-2660 Firmware	<= 1.15rc131b	—
Dlink	Dap-2690 Firmware	< 3.20rc115	—
Dlink	Dap-2690 Firmware	3.20rc115	Beta
Dlink	Dap-2695 Firmware	<= 1.20rc093	—
Dlink	Dap-3320 Firmware	< 1.05rc027	—
Dlink	Dap-3320 Firmware	1.05rc027	Beta
Dlink	Dap-3662 Firmware	< 1.05rc069	—
Dlink	Dap-3662 Firmware	1.05rc069	Beta

References

https://github.com/zyw-200/EQUAFL/blob/main/dlink-email-cve.pdfExploit, Third Party Advisory
https://github.com/zyw-200/EQUAFL/blob/main/dlink-email-cve2.pdfThird Party Advisory
https://www.dlink.com/en/security-bulletin/Vendor Advisory
https://github.com/zyw-200/EQUAFL/blob/main/dlink-email-cve.pdfExploit, Third Party Advisory
https://github.com/zyw-200/EQUAFL/blob/main/dlink-email-cve2.pdfThird Party Advisory
https://www.dlink.com/en/security-bulletin/Vendor Advisory

Timeline

Published: Aug 10, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-28838?

How severe is CVE-2021-28838?

CVE-2021-28838 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 2.16% probability of exploitation in the next 30 days.

How do I fix CVE-2021-28838?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-28838?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST