CVE-2026-7747
Buffer Overflow in Totolink N300RH Router
Publication date: 2026-05-04
Last updated on: 2026-05-04
Assigner: VulDB
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| totolink | n300rh | 3.2.4-b20220812 |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-119 | The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data. |
| CWE-120 | The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer. |
Attack-Flow Graph
AI Powered Q&A
How can this vulnerability be detected on my network or system? Can you suggest some commands?
This vulnerability affects the loginauth function of the /cgi-bin/cstecgi.cgi file in Totolink N300RH 3.2.4-B20220812. Detection involves monitoring for attempts to manipulate the Password argument remotely, which can cause a buffer overflow.
Since the exploit targets a specific CGI endpoint, you can detect potential exploitation attempts by inspecting HTTP requests to /cgi-bin/cstecgi.cgi, especially those containing the Password parameter.
- Use network monitoring tools like tcpdump or Wireshark to capture HTTP traffic targeting the device and filter for requests to /cgi-bin/cstecgi.cgi.
- Example tcpdump command to capture such traffic: tcpdump -i <interface> -A 'tcp port 80 and (((ip dst <device_ip>) and (tcp[((tcp[12:1] & 0xf0) >> 2):4] = 0x47455420)))'
- Use grep or similar tools on web server logs to search for suspicious or malformed Password parameters in requests to /cgi-bin/cstecgi.cgi.
What immediate steps should I take to mitigate this vulnerability?
Immediate mitigation steps include restricting remote access to the affected device, especially blocking access to the /cgi-bin/cstecgi.cgi endpoint.
Since the vulnerability allows remote exploitation without authentication, it is critical to isolate the device from untrusted networks until a patch or update is applied.
- Disable remote management or remote access features on the Totolink N300RH device.
- Apply any available firmware updates from the vendor that address this vulnerability.
- Monitor network traffic for exploitation attempts and consider implementing intrusion detection/prevention systems to block suspicious requests.
Can you explain this vulnerability to me?
This vulnerability is a security flaw found in the Totolink N300RH router firmware version 3.2.4-B20220812. It affects the loginauth function within the /cgi-bin/cstecgi.cgi file, specifically in the Parameter Handler component. The flaw allows an attacker to manipulate the Password argument, causing a buffer overflow. This buffer overflow can be exploited remotely, meaning an attacker does not need physical access to the device to launch an attack.
How can this vulnerability impact me? :
Exploiting this vulnerability can lead to severe consequences because it allows remote attackers to execute arbitrary code or cause a denial of service on the affected device. Given the high CVSS scores (up to 10.0 in version 2.0), the impact includes complete compromise of confidentiality, integrity, and availability of the device. Attackers could potentially take full control of the router, intercept or manipulate network traffic, disrupt network services, or use the device as a foothold for further attacks.